A microprocessor is a processor whose components have been miniaturized sufficiently to be grouped in a single integrated circuit. Functionally, the processor is part of a computer that executes instructions and processes data programs.
Description
Until the early 1970s, various electronic components forming a processor that could fit on a single integrated circuit. It should therefore be placed on multiple integrated circuits. In 1971, the American company Intel succeeds, for the first time, placing all the transistors that constitute a processor on a single integrated circuit giving rise to microprocessor.
This miniaturization has enabled: increases the operating capacity of processors, by reducing the distances between components, among others; reduce costs through the replacement of several circuits with a single one among others; increase reliability, by deleting connections between components of the processor, it removes one of the main vectors of failure; computers to create much smaller: micro-computers; reduce energy consumption.
The main characteristics of a microprocessor are: The set of instructions it can execute. Examples of instructions that a microprocessor can perform: add two numbers, compare two numbers to determine if they are equal, compare two numbers to determine which is larger, multiply two numbers, A processor can execute tens or even hundreds or thousands of different instructions.
The complexity of its architecture. This complexity is measured by the number of transistors contained in the microprocessor. Over the microprocessor contains transistors, the more it can perform complex operations, and / or treating large numbers.
The number of bits that the processor can handle whole. The first microprocessors could handle more than 4 bits at once. They had to execute multiple instructions to add the numbers 32 or 64 bits. The current microprocessors (in 2007) can handle 64-bit numbers together. The number of bits is directly related to the ability to handle large numbers quickly, or numbers of high precision (number of decimal places).
Clock speed. The role of the clock is clocking the speed of the microprocessor work. The higher the clock speed increases, the microprocessor carries out instructions in a second.
All this is theoretical, in practice, as the processor architecture, the number of clock cycles to perform an elementary operation can vary from one cycle to several dozen per unit of execution (typically on a standard processor) . For example, processor A 400 MHz may be faster than him other B 1 GHz, depending on their respective architectures.
The combination of the above characteristics determines the power of the microprocessor. The power of a microprocessor is expressed in Millions of Instructions Per Second (MIPS). In the 1970s, microprocessors were doing less than one million instructions per second, the current processors (in 2007) can carry more than 10 billion instructions per second.
History
The microprocessor was invented by two engineers from Intel: Marcian Hoff (aka Ted Hoff) and Federico Faggin. Marcian Hoff made the architecture of the microprocessor (block architecture and a set of instructions) in 1969. Federico Faggin invented the microprocessor design (new design methodology for chip and logic, using for the first time on silicon gate technology developed by him in 1968 at Fairchild, circuit design and logic; new layout and several new technical solutions) in 1970. Federico Faggin also led the design of the first microprocessor to its market introduction in 19,714.
In 1990, Gilbert Hyatt has claimed the patent of the microprocessor based on a patent he had filed in 1970. Recognition of prior patent Hyatt would have enabled him to claim royalties on all microprocessors manufactured by the world. However, Hyatt's patent was invalidated in 1995 by the U.S. Patent Office, on the basis that the microprocessor is described in the patent application had not been done, and would not, could the be with the technology available at the time of filing the patent.
The first microprocessor market, November 15, 1971, is the Intel 4004 4-bit. It was followed by the Intel 8008. This microprocessor was originally used to manufacture integrated graphics in text mode, but considered too slow for the client who requested the design, it became a general purpose processor. These processors are the precursors of the Intel 8080, Zilog Z80, and future Intel x86 family.
The following table describes the main features of microprocessors manufactured by Intel, and shows their rapid evolution in both increasing the number of transistors in circuit miniaturization and increasing power. Keep in mind that if this table describes the evolution of Intel products, changes in competitors' products has followed more or less early or late the same course.
A computer program is, in essence, a stream of instructions executed by a processor. Each instruction requires several clock cycles, the instruction is executed in as many steps as necessary cycles. The sequential microprocessors running the following statement when they finish the current instruction. In the case of ILP, the microprocessor can process several instructions at the same clock cycle, provided that these do not mobilize different instructions simultaneously a single internal resource. In other words, the processor executes instructions in sequence, and are not dependent on one another, at various stages of completion. This queue is called future execution pipeline. This mechanism was first implemented in the 1960s by IBM.
The most advanced processors running at the same time as they have instructions to pipelines, provided that all instructions execute in parallel are not interdependent, that is to say that the outturn of each of them does not alter the conditions of implementation of one another.Processors of this type are called superscalar processors. The first computer to be equipped with this type of processor was Seymour Cray's CDC 6600 in 1965. The Pentium is the first superscalar processors for PC compatible.
Today, designers of processors are not looking simply to run multiple independent instructions simultaneously, they seek to optimize the execution time of all instructions. For example, the processor can sort the instructions so that all its pipelines contain instructions independent.This mechanism is called the performance out-of-order. This type of processor has become the engine for general public from the 1980s until the years 19905. The canonical example of such a pipeline is that of a RISC processor, in five steps. The Intel Pentium 4 has 35 floors of pipeline6. A compiler optimized for this kind of processor will provide a code that will run faster. To avoid loss of time due to pending new instructions, and especially within the context reloading between each change of threads, fondeurs7 added to their processors optimization methods that threads can share the pipeline, caches and registers. These processes, collectively known Simultaneous Multi Threading, have been developed in the 1950s. By cons, for higher performance, compilers should take into account these processes, we must re-compile the programs for these types of processors. Intel began to produce the early 2000s, the SMT processors that run at two tracks. These processors, Xeon processors can simultaneously execute two threads that share the same pipelines, caches and registers. Intel called this two-way SMT:
Hyperthreading. Super-threading is, in turn, an SMT in which multiple threads also share the same resources, but these threads only run one after the other and not simultaneously. Have long existed the idea of multiple processors to coexist within a single component, such as System on Chip. This was, for example, to add to the processor, FPU, DSP, or a cache memory, possibly even the entire components found on a motherboard. Processors using two or four cores are therefore emerged, such as the IBM POWER4 released in 2001. They have the technologies mentioned previously. Computers that have this type of processors are cheaper than buying an equivalent number of processors, however, the performances are not directly comparable, it depends of the problem. Specialized APIs have been developed to make the best use of these technologies, such as the Intel Threading Building Blocks.
Date: the year of the microprocessor market.
Name: the name of the microprocessor.
Number of transistors: the number of transistors contained in the microprocessor.
Manufacturing process (μm): the diameter (in micrometers) of the smallest wire connecting two components of the microprocessor. In comparison, the thickness of a human hair is 100 microns.
Clock frequency: the frequency of the clock of the motherboard that the CPU speed. MHz = million (s) of cycles per second. GHz = billion (s) of cycles per seconds.
Width of data: the first number indicates the number of bits on which a transaction is made. The second number indicates the number of bits transferred between both memory and microprocessor.
MIPS: the number of million instructions performed by the microprocessor in a second.
1971 4004 2300108 kHz 4 bit / 4-bit bus
1974 8080 6 000 6 2 MHz 8 bit / 8 bit bus 0.64
1979 8088 29 000 May 3 MHz 16-bit / 8 bit bus 0.33
1982 80286 134 000 1,5 6-16 MHz (20 MHz AMD) 16-bit bus bits/16 1
1985 80386 275 000 1.5 16-40 MHz 32-bit bus 5 bits/32
1989 80486 1 200 000 1 16-100 MHz 32-bit bus 20 bits/32
Pentium 3.1 million in 1993 from 0.8 to 0.28 60-233 MHz 32-bit bus 100 bits/64
Pentium II 1997 7,500,000 0.35 to 0.25 233-450 MHz 32-bit bus 300 bits/64
1999 Pentium III 9.5 million from 0.25 to 0.13 450-1 400 MHz 32-bit bus 510 bits/64
Pentium 4 2000 42,000,000 0.18 to 0.065 from 1.3 to 3.8 GHz 32-bit bus bits/64 1700
2004 Pentium 4D "Prescott" 125,000,000 0.09 to 0.065 2.66 to 3.6 GHz 32-bit bus bits/64 9000
Core 2 Duo ™ 2006 291 000 000 0.065 2.4 GHz (E6600) 64-bit bus bits/64 22,000
Core ™ 2 Quad 2007 2 * 291 000 000 0.065 3 GHz (Q6850) 64-bit bus bits/64 2 * 22 000 (?)
2008 Core 2 ™ Duo (Penryn) 410 000 000 0.045 3.33 GHz (E8600) 64-bit bus bits/64 ~ 24,200
2008 Core ™ 2 Quad (Penryn) 2 * 410 000 000 0.045 3.2GHz (QX9770) 64-bit bus bits/64 ~ 2 * 24 200
2008 Intel Core i7 (Nehalem) 731 000 000 0.045 (2008)
0.032 (2009) 2.66GHz (Core i7 920)
3.33GHz (Core i7 Ext. Ed. 975) 64-bit bus bits/64?
2009 Intel Core i5/i7 (Lynnfield) 774000000 0.045 (2009)
2.66GHz (Core i5 750)
2.93GHz (Core i7 870) 64-bit bus bits/64?
2010 Intel Core i7 (Gulftown) 1170000000 0.032 3.33GHz (Core i7 980X) 64-bit bus bits/64?
Families of Microprocessors
Microprocessors are usually grouped into families, according to the set of instructions they execute. This game includes instructions, often a common basis for the entire family, often the most recent microprocessors families have new instructions. Backward compatibility within a family is not always assured. For example a program known for writing x86 compatible processor 80386, which allows memory protection, could not not work on earlier processors, but works on all newer processors (eg a Core Duo or Athlon d AMD).
Families of Microprocessors
The family best known by the general public is the x86 family, developed primarily by companies Intel (maker of the Pentium), AMD (Athlon manufacturer), VIA and Transmeta. The first two companies dominate the market and they make the largest share of microprocessors for personal computers compatible PC. Intel also supplies the microprocessors for the Macintosh computers since 2006.
PowerPC microprocessors from IBM and Motorola team until 2006 Macintosh computers (made by Apple). These microprocessors are also used in the P-series servers and IBM in various embedded systems. In the field of gaming consoles, the PowerPC microprocessors derivatives equip the Wii (Broadway), GameCube (Gekko) Xbox 360 (three hearts secondary named Xenon). The PlayStation 3 is equipped with the Cell microprocessor, derived from POWER4, PowerPC architecture close.
The company's 6502 MOS Technology was used to produce the famous Apple II.
The Zilog Z80 microprocessor has been widely used in the 1980s in designing the first personal computers as the 8-bit Radio Shack TRS-80, the Sinclair ZX80, ZX81, ZX Spectrum, Apple II, with a daughter card, the Standard MSX, Amstrad CPC and the latest in embedded systems.
Family 6800 the company Motorola.
The family 68000 (also known m68k) Motorola animated the old Macintosh, Sega Genesis, Atari ST and Commodore Amiga. Derivatives (Dragonball, Coldfire) are still used in embedded systems.
Among the smaller families known to the general public:
The family Sparc animates most of the servers and workstations from Sun Microsystems, though more and more new products are made on x86.
The family of HP PA-RISC and VLSI Technology, animates the old servers and workstations from HP, now replaced by the family IA-64
IA-64 family of HP and Intel, brings 64-bit servers and workstations from HP
The family runs MIPS workstations from Silicon Graphics, game consoles like the PSone, Nintendo 64 and embedded systems, as well as Cisco routers. This is the first family to offer a 64-bit architecture with the R4000 in 1991. The Chinese foundry Loongson processors are based on a new generation of MIPS Technologies, used in supercomputers and low-power computers.
The ARM family is nowadays only used in embedded systems, including many PDAs and smartphones, it has previously been used by Archimedes and Acorn for his RiscPC.
The animated family DEC Alpha computers in December, then taken over by Compaq, which HP has definitely stopped.
Fast Instruction Execution in Operating Frequency
The microprocessors are clocked by a clock signal (oscillating signal requiring a regular rhythm to the circuit). In the mid-1980s, this signal had a frequency of 4 to 8 MHz. In the 2000s, this frequency is 4 GHz. Over this frequency, the higher the microprocessor can execute at a high rate basic instructions of programs.
Increasing the frequency drawbacks: higher it is, the processor consumes more power, and it heats more: it means having a CPU cooling solution developed; particular frequency is limited by the switching time of logic gates: it is necessary between two formidable clock, the digital signals have time to travel all the way necessary for the execution of the statement expected and for faster processing, requires action on many parameters (size of a transistor, electromagnetic interactions between the circuits, etc..) it becomes increasingly difficult to improve (and ensuring reliability operations).
Overclocking
The overclocking is to force the increase in the frequency of the clock signal from the microprocessor (compared to the manufacturer's recommendations) in order to execute more instructions each second.
Optimization of the Execution Path
Current microprocessors are optimized to run more than one instruction per clock cycle, they are microprocessors with threads in parallel. In addition they have procedures that "anticipate" the following instructions with the help of statistics.
In the race to the power of microprocessors, two optimization methods are in competition:
The RISC (Reduced Instruction Set Computer, a simple set of instructions) and fast with simple instructions for standard size, easy to manufacture and which you can mount the clock frequency without too many technical difficulties.
Technology CISC (Complex Instruction Set Computer), each complex instruction requires more clock cycles, but which has at its heart a lot of instructions pre-wired.
However, with decreasing size of computer chips and faster clock rates, the distinction between RISC and CISC has almost completely disappeared. Where families trenches existed, are now observed as a microprocessor RISC provides internal structure of power while remaining compatible with type use CISC (Intel x86 family has been transitioning from an organization initially very typical a structure CISC. Currently it uses a very fast heart RISC, based on a rearrangement of the code on the fly), implemented in part through caches become larger, with up three levels.
Structure of a Microprocessor
Main article: Architecture and processor microarchitecture.
The central unit of a microprocessor includes mainly:
an arithmetic logic unit (ALU) which performs operations;
registers that allow the microprocessor to store data temporarily;
a control unit which controls the entire microprocessor based on the instructions of the program.
Some records have a very specific role:
register status flag (flags), this register gives the status of the microprocessor at any time, it can only be read;
the program counter (PC Program Counter) contains the address of the next instruction to execute;
the stack pointer (SP Stack Pointer) is the pointer to a special area of memory called the stack where the arguments are stored sub-programs and return addresses.
Only the Program Counter is essential, there are (few) processors having no status register or not stack pointer (eg NS32000).
The control unit can also be decomposed:
register instruction, stores the instruction code to execute;
the decoder decodes the instruction;
the sequencer executes the instruction, he will control all organs of the microprocessor.
Manufacture of Microprocessors
The fabrication of a microprocessor is essentially identical to that of any integrated circuit. It follows therefore a complex process. But the enormous size and complexity of most microprocessors tends to increase further the cost of the operation.
Moore's Law
Moore's Law, which states that the degree of integration of microprocessors doubles every 18 months, also indicates that production costs at the same time doubling the degree of integration. The manufacturing of microprocessors is now considered one of the two factors increase the capacity of manufacturing facilities (with the constraints related to the manufacture of large-capacity storage). The fineness of the engraving industry reached 45 nm 20 068. By further reducing the fine engraving, smelters face to the rules of quantum mechanics.
Multiple Parallel Processors
According to the operating system, the current trend is to install multiple parallel processors and multiple tasks where the growing importance of trade-offs between process functions (eg hyper threading). In fact, the superscalar architecture (paralleling of tasks in an execution unit) of current processors currently does more multi-threading as used. However, processors that require multiple cores should be studied closely the distribution of tasks between them so that we do not see see a slowdown in transactions, this is called the affinities between processors (processor affinity).
Security and Rental
There are many integration projects at the heart of the microprocessor functions to prevent unauthorized copying of files (DRM). The consortium Trusted Computing Group, in particular, has already created chips to create a "zone of confidence" in the computer system, using a specific identification chip. Some computer models, such as IBM laptops already include such chips. The next generation of this technology will probably be integrated in the CPUs of computers. These technologies are decried, especially by supporters of free software, for which they have a potential of civil liberties. Indeed, combined with an operating system for this purpose, for example derived from Microsoft Project NGSCB, this technology enables the trusted third party (the provider that will check the validity of the system components) to access distance inside the computer, or even prevent the execution of some operations on it.
August 2, 2010
Apple Computer
Apple, formerly Apple Computer (NASDAQ: AAPL) is an American multinational computer company, whose headquarters is located in Cupertino, Silicon Valley. The firm became famous with his Apple II personal computer (1977), then the Macintosh line (1984) 2. In 2001, Apple has diversified its activities by venturing into the music industry with the iPod and the iTunes Store (2003) two products designed for digital music, then to the mobile with the iPhone (2007). The brand is known for its simple user interface and sleek design of its products, and also for its ability to inform the public of existing technologies by making them accessible even to a lay audience. This was the case with the graphic interface with windows, mouse and more recently the Multitouch screen.
History of Apple
Apple was established on 1 April 1976 in Cupertino, then incorporated as a company Jan. 3, 1977. Some years before its inception the company as it exists in 2010, Apple has had various facets related to the evolution of the computing world, from a world without personal computers to a company of twenty-first century by interconnected through fixed and mobile devices. His story is particularly related to that of one of its co-founders, Steve Jobs, forced to leave the firm in 1985, then rehired in December 1996 before becoming CEO of the company in 1997. Among the key products Apple has experienced since its inception, are the Apple I and II, the Macintosh, iPod, iPhone and iPad.
The "Apple culture"
The meetings with the public. Apple has always favored a technical trade reconciliation with its consumers and potential consumers. This is part of an overall marketing technique aimed, among other things, to give the impression to the consumer to be part of a community of users close to the computer company. There are several important annual meetings between Apple, its customers, developers and especially the press. Each opened with a video projection where Steve Jobs presents the financial results of the company and generally new products. The importance of these major meetings fluctuates, and in 2000, the three most important were the Macworld Expos New York (now defunct), San Francisco and Tokyo.
Macworld Conference & Expo San Francisco takes place in January. Apple is mostly announced new products geared toward the general public. The last took place from 14 to 18 January 2008. The MacWorld Expo 2009 was the last and took place without Steve Jobs, replaced by Phil Schiller (Vice-President of the company). According to an official statement, the website and their stores are sufficient to ensure the success of the brand.
Worldwide Developers Conference (WWDC): annual event of great importance, it was then that Apple would unveil the main novelties of the year (usually software oriented and professional audience). The last was held in San Francisco from June 7 to June 11, 2010 which was unveiled the iPhone 4.
Apple Expo: Launched in 1984, it took place in Paris (Porte de Versailles) in September, is the first appointment Mac in Europe, and the first rendezvous IT & Digital France. Its importance in communicating the publisher has fallen in recent years: Apple has ceased to hold a keynote since 2006 and announced his departure from the show's 2008 edition, held from 17 to 20September 2008.
Thus, Apple has phased out all these conferences, in favor of cheaper ways of rapprochement with the users, such as Apple Store and their official website. However, the decision of this tradition gave rise to a certain sadness among fans of the brand, who see the evaporation of the friendly atmosphere that maintaining old Apple. Still, unless Apple continues to hold regular keynote to present major new products.
The first version of the logo represented Isaac Newton under an apple tree from which hung. Very quickly, it is replaced by an apple in the colors of the rainbow in the sky bitten on the right side, designed by Rob Janoff. The visual features of the logo appear as the result of a systematic walk-cons made from the logo of IBM, Apple's main competitor at the time. Indeed, the silhouette of the apple logo gives Apple a simple configuration and understood in a general block, while IBM is in the form of a triptych. Secondly, the shapes of the fruit are completely constructed from curves, straight-based IBM. Third, the chromatic sequence type ABBA Apple: warm colors in the center, emphasizing the pinch of the apple cold outside. The sequence in the case of IBM is repetitive (BABA) and two colors: the bands are disjoint cool colors like blue. The apple is bitten not to be confused with the logo of Apple Corps record label founded by the Beatles but the story says that the apple is bitten not to be confused with that of a tomato.
In his history of Apple, entitled The Third Apple, Jean-Louis Gassée Alan Turing mentions several times but did not mention an iconic tribute to him there are three apples, the fruit of the tree of knowledge ( myth of Adam and Eve), Isaac Newton's apple (besides the organizer called the Apple Newton), and finally the apple of Apple. The foundation of Apple prone to myths, the newspaper reported SVM Mac also the legend according to which the poverty in which both Steve lived in their infancy have led to high consumption of apples, Steve Jobs has a particular liking for McIntosh , which tended to get a tan.
Another legend says that Steve had two months of delay to give a name to his business and then threatened to call his company "Apple Computer" if his colleagues did not do him a good name suggestion before 17 pm. Finding nothing the company became Apple. Another reason mentioned was the desire to appear before its competitors in alphabetical order, the first time since the Atari.
Rob Janoff met Steve Jobs for the first time when he worked in Palo Alto, in the PR firm Regis McKenna. He was in charge of designing a logo for a friend of his boss, Steve Jobs. "For inspiration, the first thing I did was go to the supermarket to buy a bag of apples and slice them," recalls Janoff. The fruit of his work: an apple monochromatic 2D, with a small bite on the right side. Jobs liked the concept, although he suggested would have been better a bit more colorful. Janoff's boss disagreed, insisting that a black logo would be less expensive to print.But Jobs was determined, arguing that the color was the key to humanizing the company "continues Janoff.
From 1997 to 2001 the logo changed again: the form remains the same (although sometimes it is adorned with a slight relief effect), but the reason rainbow is replaced by a monochrome tone, varying by product door. The battle with IBM was over. Apple is now a symbol catchy, as is Sony or Nike. This change is intended to give the company an image more in line with its ambitions in the professional market. The apple colorful, evoking for many the hippie movement, the sounds at the opening of windows or the "Happy Mac" (previously shown at startup of the Macintosh), like other icons of Susan Kare, had gone out of fashion, while logo embossed gloss gives the brand an image of luxury and quality. On computers, the iMac is the first to replace the apple with a monochrome color on its hull. And the operating system Mac OS X which completes the work by making monochrome apple at the corner of the menu bar of the computer.
Between marketing, innovation and choice
Apple has a reputation for providing systems easy to use, intuitive and integrates perfectly stable operating system, which in turn fits perfectly with the machine. This is due to Apple's closed policy, which chooses its own hardware and peripheral products. This is probably the main advantage of vertical product strategy led by the mark, despite the drawbacks of such a strategy for the customer and the company. Apple has upgraded its distribution network-house, opening his own store, Apple stores.Although this initiative to enter the field of retailing has received a mixed reception from the independent dealers, this strategy proved successful. Indeed, sites promoting "Apple brand" responsible for a concept design that combines technology and simplicity accents, Apple Stores contribute to the identity of the brand. Naomi Klein identifies in his book No Logo as one of the most sophisticated of modern times, tied with Nike. In 1984, Apple gets George Orwell in an advertisement against IBM. Later, Gandhi Think different testifies in favor of the mark in its publicités5.
Organization
It alleges that Apple's model of vertical development, which goes against the requirements of most economists, especially for IT. Despite this, the company released a profit. Apple is also criticized because it depends heavily on the personality that directs it, especially during two eras of Jobs. Some argue that Steve Jobs is the subject of a cult of personality, or at least between some elements of such a cult in its relationship with its customers, and it maintains about him a field distortion of reality.
Apple is still criticized for a closed architecture, and its refusal standards: we use the term syndrome of not-invented-here. This criticism is out of place, however, most electronic components of its computers are common to the entire computer industry. In addition, the operating system utilizes a number of popular technologies (1-4 MPEG, OpenGL, programming free). Finally, the time when the policy choice of technology existed, it was not objectionable in itself, because research and innovation are engines of development, each company seeks to recoup its research costs and development by setting market his inventions.In addition, several technologies Apple first used by Apple are then generalized in the personal computer (FireWire ZeroConf (Hello, ex-Apple Rendezvous)). Similarly, Apple has enabled and accelerated the adoption of innovations by generalizing from a blow to its range (3.5-inch floppy disks, SCSI, USB, Wi-Fi (AirPort)).
Some analysts criticize the competition within Apple itself, between different programmers programming environments, those in Cocoa, NeXTSTEP heirs, and those of Carbon derived from Mac OS 9. This rivalry is seen as cons-productive, as was his time in the rivalry between the teams Apple II and Macintosh. A less commonly heard criticism [ref. necessary], because on most businesses and individuals, concerning the lack of a "Roadmap" (Planning announced) on Apple marked its software technologies. IT departments of large companies expect from a publisher to clearly announce what will tender its software in the next five years, in order to make investment choices in the medium term. However, the allegation that Apple is not really announce what will be the stages of its evolution beyond a year, unlike its competitors like Microsoft. A simple example is if, for the abrupt announcement of the abandonment of PowerPC processors from IBM / Motorola in favor of those from Intel: publishers need to update their applications, while owners of ParkMicro will have to pay these updates, and will manage two lines of machines. An announcement earlier had allowed them to anticipate the phenomenon, in planning the park renewals based on the torque hardware / software in order to avoid additional costs for updating.
The cancellation of the regular development of promising technologies yet (eg OpenDoc) has also left on the roadside of developers, tired of investing time and money in "dead ends". As a result, the number of independent developers and publishers declined during the 1990s. This criticism is outdated since the introduction of Mac OS X, which has returned to the bosom of many Apple developers from the Unix / Linux and free software.
Moreover, the management system of after-sale in Europe, told a single provider for laptops and G5, proved to be one of the weaknesses of the trading system Apple. Following significant delays in the early 2000s, the service provider went bankrupt in early 2005, forcing Apple to use technicians to the retailers and causing further delays in repairs.
Price
Finally, Apple is often accused of pursuing a policy of price too high. The price of a Macintosh could often be twice that of a PC / IBM compatible in the 1980s, or even three times in the 1990s after the advent of the Pentium. This policy of high prices has probably hampered the development of the Macintosh in favor of the PC and consumer multimedia computers of the era, such as the Amiga and the Atari. Today, Apple posted rates are often more expensive and represent a barrier for many users wishing to make the "switch", that is to say, from Windows to Mac OS X, even if the output Mac mini is an initiative which again opens a field in the area.
It is true that the margins applied by Apple are much higher than those generally practice in this area (between 25% and 30% gross margin in the early 2000s, when some PC makers are content to 8% or less). However, a Gartner Group study commissioned by Apple Australia and distributed by him in the press in 2002, stated that the TCO (Total Cost of Ownership) or TCO, that is to say the total cost of computer equipment when you add optional hardware, software (licenses), support (etc.) is lower with a Mac than on a PC running Windows. Balanced review later by Gartner, which said that the information contained in the report did not reflect the editorial position and were intended for internal use at Apple, corresponding to a specific scenario.
Environment
In late 2006 and early 2007, Apple was ranked twice by Greenpeace as the last in a ranking of fourteen companies manufacturing electronic products, on criteria such as environmental waste management, recycling of obsolete products, the use of polluting components or communication to the general public on these sujets6, 7. Apple denies this classification in an open letter from Steve Jobs8. The company says make for several years in shares environnemental9. Sites devoted to the Macintosh have on several occasions discussed the environmental aspects of Apple and the use of the image of Apple by Greenpeace10, 11.Greenpeace France has recently shown (May 2007) by organizing a demonstration outside an Apple dealer even though the international section of the association has rebounded in early May on Apple's ranking with an average of 5 / 10 following the letter of Steve Jobs12. In March 2008 Apple is located in mid-table, with a score of 7 / 1013.
The Cupertino company has responded fairly quickly but not for the iPhone. In announcing the new iMacs August 7, 2007, Steve Jobs's Apple event begins in these words: "Ladies and gentlemen, here is the new iMac, it is much more environmentally friendly and recyclable ...". The white polycarbonate and is replaced by anodized aluminum components and glass facades. The iPhone has also been criticized by Greenpeace, which denounced the extremely toxic materials inside it. Apple has not responded and seems in no hurry to make its iPhone more environmentally friendly. Indeed, Apple has replaced the aluminum hull aft of the iPhone by a polycarbonate shell for iPhone 3G.
History of Apple
Apple was established on 1 April 1976 in Cupertino, then incorporated as a company Jan. 3, 1977. Some years before its inception the company as it exists in 2010, Apple has had various facets related to the evolution of the computing world, from a world without personal computers to a company of twenty-first century by interconnected through fixed and mobile devices. His story is particularly related to that of one of its co-founders, Steve Jobs, forced to leave the firm in 1985, then rehired in December 1996 before becoming CEO of the company in 1997. Among the key products Apple has experienced since its inception, are the Apple I and II, the Macintosh, iPod, iPhone and iPad.
The "Apple culture"
The meetings with the public. Apple has always favored a technical trade reconciliation with its consumers and potential consumers. This is part of an overall marketing technique aimed, among other things, to give the impression to the consumer to be part of a community of users close to the computer company. There are several important annual meetings between Apple, its customers, developers and especially the press. Each opened with a video projection where Steve Jobs presents the financial results of the company and generally new products. The importance of these major meetings fluctuates, and in 2000, the three most important were the Macworld Expos New York (now defunct), San Francisco and Tokyo.
Macworld Conference & Expo San Francisco takes place in January. Apple is mostly announced new products geared toward the general public. The last took place from 14 to 18 January 2008. The MacWorld Expo 2009 was the last and took place without Steve Jobs, replaced by Phil Schiller (Vice-President of the company). According to an official statement, the website and their stores are sufficient to ensure the success of the brand.
Worldwide Developers Conference (WWDC): annual event of great importance, it was then that Apple would unveil the main novelties of the year (usually software oriented and professional audience). The last was held in San Francisco from June 7 to June 11, 2010 which was unveiled the iPhone 4.
Apple Expo: Launched in 1984, it took place in Paris (Porte de Versailles) in September, is the first appointment Mac in Europe, and the first rendezvous IT & Digital France. Its importance in communicating the publisher has fallen in recent years: Apple has ceased to hold a keynote since 2006 and announced his departure from the show's 2008 edition, held from 17 to 20September 2008.
Thus, Apple has phased out all these conferences, in favor of cheaper ways of rapprochement with the users, such as Apple Store and their official website. However, the decision of this tradition gave rise to a certain sadness among fans of the brand, who see the evaporation of the friendly atmosphere that maintaining old Apple. Still, unless Apple continues to hold regular keynote to present major new products.
The first version of the logo represented Isaac Newton under an apple tree from which hung. Very quickly, it is replaced by an apple in the colors of the rainbow in the sky bitten on the right side, designed by Rob Janoff. The visual features of the logo appear as the result of a systematic walk-cons made from the logo of IBM, Apple's main competitor at the time. Indeed, the silhouette of the apple logo gives Apple a simple configuration and understood in a general block, while IBM is in the form of a triptych. Secondly, the shapes of the fruit are completely constructed from curves, straight-based IBM. Third, the chromatic sequence type ABBA Apple: warm colors in the center, emphasizing the pinch of the apple cold outside. The sequence in the case of IBM is repetitive (BABA) and two colors: the bands are disjoint cool colors like blue. The apple is bitten not to be confused with the logo of Apple Corps record label founded by the Beatles but the story says that the apple is bitten not to be confused with that of a tomato.
In his history of Apple, entitled The Third Apple, Jean-Louis Gassée Alan Turing mentions several times but did not mention an iconic tribute to him there are three apples, the fruit of the tree of knowledge ( myth of Adam and Eve), Isaac Newton's apple (besides the organizer called the Apple Newton), and finally the apple of Apple. The foundation of Apple prone to myths, the newspaper reported SVM Mac also the legend according to which the poverty in which both Steve lived in their infancy have led to high consumption of apples, Steve Jobs has a particular liking for McIntosh , which tended to get a tan.
Another legend says that Steve had two months of delay to give a name to his business and then threatened to call his company "Apple Computer" if his colleagues did not do him a good name suggestion before 17 pm. Finding nothing the company became Apple. Another reason mentioned was the desire to appear before its competitors in alphabetical order, the first time since the Atari.
Rob Janoff met Steve Jobs for the first time when he worked in Palo Alto, in the PR firm Regis McKenna. He was in charge of designing a logo for a friend of his boss, Steve Jobs. "For inspiration, the first thing I did was go to the supermarket to buy a bag of apples and slice them," recalls Janoff. The fruit of his work: an apple monochromatic 2D, with a small bite on the right side. Jobs liked the concept, although he suggested would have been better a bit more colorful. Janoff's boss disagreed, insisting that a black logo would be less expensive to print.But Jobs was determined, arguing that the color was the key to humanizing the company "continues Janoff.
From 1997 to 2001 the logo changed again: the form remains the same (although sometimes it is adorned with a slight relief effect), but the reason rainbow is replaced by a monochrome tone, varying by product door. The battle with IBM was over. Apple is now a symbol catchy, as is Sony or Nike. This change is intended to give the company an image more in line with its ambitions in the professional market. The apple colorful, evoking for many the hippie movement, the sounds at the opening of windows or the "Happy Mac" (previously shown at startup of the Macintosh), like other icons of Susan Kare, had gone out of fashion, while logo embossed gloss gives the brand an image of luxury and quality. On computers, the iMac is the first to replace the apple with a monochrome color on its hull. And the operating system Mac OS X which completes the work by making monochrome apple at the corner of the menu bar of the computer.
Between marketing, innovation and choice
Apple has a reputation for providing systems easy to use, intuitive and integrates perfectly stable operating system, which in turn fits perfectly with the machine. This is due to Apple's closed policy, which chooses its own hardware and peripheral products. This is probably the main advantage of vertical product strategy led by the mark, despite the drawbacks of such a strategy for the customer and the company. Apple has upgraded its distribution network-house, opening his own store, Apple stores.Although this initiative to enter the field of retailing has received a mixed reception from the independent dealers, this strategy proved successful. Indeed, sites promoting "Apple brand" responsible for a concept design that combines technology and simplicity accents, Apple Stores contribute to the identity of the brand. Naomi Klein identifies in his book No Logo as one of the most sophisticated of modern times, tied with Nike. In 1984, Apple gets George Orwell in an advertisement against IBM. Later, Gandhi Think different testifies in favor of the mark in its publicités5.
Organization
It alleges that Apple's model of vertical development, which goes against the requirements of most economists, especially for IT. Despite this, the company released a profit. Apple is also criticized because it depends heavily on the personality that directs it, especially during two eras of Jobs. Some argue that Steve Jobs is the subject of a cult of personality, or at least between some elements of such a cult in its relationship with its customers, and it maintains about him a field distortion of reality.
Apple is still criticized for a closed architecture, and its refusal standards: we use the term syndrome of not-invented-here. This criticism is out of place, however, most electronic components of its computers are common to the entire computer industry. In addition, the operating system utilizes a number of popular technologies (1-4 MPEG, OpenGL, programming free). Finally, the time when the policy choice of technology existed, it was not objectionable in itself, because research and innovation are engines of development, each company seeks to recoup its research costs and development by setting market his inventions.In addition, several technologies Apple first used by Apple are then generalized in the personal computer (FireWire ZeroConf (Hello, ex-Apple Rendezvous)). Similarly, Apple has enabled and accelerated the adoption of innovations by generalizing from a blow to its range (3.5-inch floppy disks, SCSI, USB, Wi-Fi (AirPort)).
Some analysts criticize the competition within Apple itself, between different programmers programming environments, those in Cocoa, NeXTSTEP heirs, and those of Carbon derived from Mac OS 9. This rivalry is seen as cons-productive, as was his time in the rivalry between the teams Apple II and Macintosh. A less commonly heard criticism [ref. necessary], because on most businesses and individuals, concerning the lack of a "Roadmap" (Planning announced) on Apple marked its software technologies. IT departments of large companies expect from a publisher to clearly announce what will tender its software in the next five years, in order to make investment choices in the medium term. However, the allegation that Apple is not really announce what will be the stages of its evolution beyond a year, unlike its competitors like Microsoft. A simple example is if, for the abrupt announcement of the abandonment of PowerPC processors from IBM / Motorola in favor of those from Intel: publishers need to update their applications, while owners of ParkMicro will have to pay these updates, and will manage two lines of machines. An announcement earlier had allowed them to anticipate the phenomenon, in planning the park renewals based on the torque hardware / software in order to avoid additional costs for updating.
The cancellation of the regular development of promising technologies yet (eg OpenDoc) has also left on the roadside of developers, tired of investing time and money in "dead ends". As a result, the number of independent developers and publishers declined during the 1990s. This criticism is outdated since the introduction of Mac OS X, which has returned to the bosom of many Apple developers from the Unix / Linux and free software.
Moreover, the management system of after-sale in Europe, told a single provider for laptops and G5, proved to be one of the weaknesses of the trading system Apple. Following significant delays in the early 2000s, the service provider went bankrupt in early 2005, forcing Apple to use technicians to the retailers and causing further delays in repairs.
Price
Finally, Apple is often accused of pursuing a policy of price too high. The price of a Macintosh could often be twice that of a PC / IBM compatible in the 1980s, or even three times in the 1990s after the advent of the Pentium. This policy of high prices has probably hampered the development of the Macintosh in favor of the PC and consumer multimedia computers of the era, such as the Amiga and the Atari. Today, Apple posted rates are often more expensive and represent a barrier for many users wishing to make the "switch", that is to say, from Windows to Mac OS X, even if the output Mac mini is an initiative which again opens a field in the area.
It is true that the margins applied by Apple are much higher than those generally practice in this area (between 25% and 30% gross margin in the early 2000s, when some PC makers are content to 8% or less). However, a Gartner Group study commissioned by Apple Australia and distributed by him in the press in 2002, stated that the TCO (Total Cost of Ownership) or TCO, that is to say the total cost of computer equipment when you add optional hardware, software (licenses), support (etc.) is lower with a Mac than on a PC running Windows. Balanced review later by Gartner, which said that the information contained in the report did not reflect the editorial position and were intended for internal use at Apple, corresponding to a specific scenario.
Environment
In late 2006 and early 2007, Apple was ranked twice by Greenpeace as the last in a ranking of fourteen companies manufacturing electronic products, on criteria such as environmental waste management, recycling of obsolete products, the use of polluting components or communication to the general public on these sujets6, 7. Apple denies this classification in an open letter from Steve Jobs8. The company says make for several years in shares environnemental9. Sites devoted to the Macintosh have on several occasions discussed the environmental aspects of Apple and the use of the image of Apple by Greenpeace10, 11.Greenpeace France has recently shown (May 2007) by organizing a demonstration outside an Apple dealer even though the international section of the association has rebounded in early May on Apple's ranking with an average of 5 / 10 following the letter of Steve Jobs12. In March 2008 Apple is located in mid-table, with a score of 7 / 1013.
The Cupertino company has responded fairly quickly but not for the iPhone. In announcing the new iMacs August 7, 2007, Steve Jobs's Apple event begins in these words: "Ladies and gentlemen, here is the new iMac, it is much more environmentally friendly and recyclable ...". The white polycarbonate and is replaced by anodized aluminum components and glass facades. The iPhone has also been criticized by Greenpeace, which denounced the extremely toxic materials inside it. Apple has not responded and seems in no hurry to make its iPhone more environmentally friendly. Indeed, Apple has replaced the aluminum hull aft of the iPhone by a polycarbonate shell for iPhone 3G.
Supercomputer
A supercomputer is a computer with an exceptionally high processing capacity and
computing power. Since its introduction in the forties to the present , the
capacity of electronic machines increases rapidly.
computing power. Since its introduction in the forties to the present , the
capacity of electronic machines increases rapidly.
The first supercomputers were built in 60 years, an average pocket calculator
now has a greater capacity. Currently (2010), the Cray XT5 Jaguar is the fastest
supercomputer. Then followed by IBM Roadrunner (2008) and the Blue Gene / L
(2004) IBM, which in turn was preceded by the Earth Simulator (2002) of NEC.
<bold>Mainframe vs. Supercomputer </bold>
One should not confuse a supercomputer with a mainframe. Both have a large
capacity, but supercomputer is the greatest. Mainframe purpose is to serve users
continuosly. They used a supercomputer can take pleasure when a system that
sometimes must be serviced, but which demanded absolute excellence if the system
is running. The focus is usually on floating point operations. Often a
supercomputer used for research work in universities or technical institutes
which at any moment only a limited number of people the system works, and each
user has their own specific applications.
<bold> Safety </bold>
A particular aspect of supercomputers is the possibility that this could be used
for encryption and decryption algorithms and to do research on the effects of
nuclear weapons. That is why USA restrict the exports of supercomputers.
<bold> Features </bold>
Supercomputers now contain multiple processors. While most (home) PC's one or
two processors, a supercomputer may contain thousands. These processors are
connected by a very fast network. Widely used for supercomputers include
Myrinet, Quadrics and InfiniBand. Some super computer like Cray, that can
develop their own network. Other common features of supercomputers, the presence
of memory and storage capacity. It is also possible to a cluster of computers to
act as a fast supercomputer. Its tasks are then distributed supercomputing on
the computers that the supercomputer. Now increasingly powerful personal
computers can also be used in a cluster.
<bold> Future </bold>
Today, increasing use of these clusters that operate using Distributed Computing
with networks such as normal (slower but much cheaper) PCs as a major
supercomputer deployment. Sometimes exceeds the computational speed of these
networks of the largest 'single' supercomputers. An example is the network of
the world scattered PCs are used in SETI search for extraterrestrial life. This
"virtual" network computers are faster and can often be measured well with the
fastest supercomputers. Some experts therefore suggest that as the networks from
which the Internet is becoming faster and gradually all the computers connected
to the Internet eventually as a single "supercomputer" will function. That would
be pointless to even have separate supercomputers to speak. For now this will
not happen because the connections between individual computers via ordinary
Internet is too slow. Especially the startup time of compounds (Latency) via
ordinary Internet yet too high.
History of Computer Technology
A computer is a machine that can process data and perform calculations much more effectively than a man can do manually. The computer can consist of mechanical, electronic, optical or other components and controlled by instructions from a computer program.
Initially, the computer essentially a tool for performing arithmetic and other mathematical calculations, but has since become an important tool in particular, automation of administrative procedures, communications, information storage and media processing. During childhood, computers were used expression Electron brain as a popular title.
With the miniaturization of electronics has the basic components of what constitutes a computer (control unit, a unit of account and with memory circuits for communications with the outside world) could be on fewer silicon plates. In its extreme form, a computer (albeit somewhat limited capacity) fit on a single silicon plate, and is then called microprocessor. For common people the word computer aimed mostly at a personal computer, but there are many other types of computers.
History of Computer Technology
Calculators have been around for centuries, but it was not until the 1900s that they became electric. Blaise Pascal invented the first mechanical calculator in 1642, which could add or subtract, and can be seen as a precursor to the computer. Three decades later designed Gottfried Wilhelm von Leibniz, a machine that also survived multiplication and division.
Reconstruction of Zuses Z1
Thereafter the development stagnated until the 1820s, when Charles Babbage presented drawings to the difference machine, essentially a mechanical computer, whose program was predetermined by the design itself. Babbage invented after the screening machine in 1834, a fully programmable mechanical computer with working memory, processor, punch card readers for input for writing and punching the hole cards. Ada Lovelace wrote the first computer programs for the analytical machine. However, part of the design of mechanical problems and was never completed.
In 1936 German engineer Konrad Zuse designed the first electromechanical computer based on electromagnetic relays, which is called Z1, and a number of other computers. The devices were destroyed in 1944 when the Allies bombed Berlin during World War II, and his work did not affect the development of later computers significantly.
The British government gave in great secrecy to build Colossus to decode German Enigma encrypted messages, a job that Alan Turing took part in. The machine was in use in 1943, but did not affect the rest of the development, because it was classified in three decades. In 1944, Howard Aiken at Harvard University created decimal computer which is called Mark I, inspired by Babbage's work.
ENIAC
John Mauchley, a physics professor at the University of Pennsylvania, with his student Presper Eckert, designed decimal computer, which is called ENIAC, on behalf of the U.S. Army to calculation of projectile paths. ENIAC, which began construction in 1943, was completed only in 1946, when the world war is over. The computer, which was based on vacuum tubes and relays, however, created great interest within the scientific community and was the beginning of a tremendous variety.
Von Neumann Architecture
John von Neumann, who has been involved in this project, realized that instead of being programmed by the settings of the relays and wiring would be stored in computer memory with data. Based on this, he created IAS machine, which was built in 1952. The same principle was also used in computer created by Maurice Wilkes Edsac 1949th. Since then, the von Neumann architecture was the prevailing principle of computer design.
Transistor-based Computers
The first generation computers were based on vacuum tubes. When John Bardeen, Walter Brattain and William Shockley at Bell Labs invented the transistor in 1948 (which they later received the Nobel Prize in physics for) this was the basis for the second generation of computers.
The first transistor-based computer was the TX-0, which was developed at MIT Lincoln Laboratory, inspired by the former MIT Project Whirlwind I from 1952. One of the engineers at the laboratory, Kenneth Olsen, who founded in December 1961 began selling the PDP-1, a commercial minicomputer similar to TX-0. PDP-1 competed primarily with IBM 7090, a transistor-based computer company from IBM, which started to become interested in computers are increasingly having previously funded Aikens Mark I. PDP -1 had admittedly only half of the performance compared to the IBM 7090, but it cost also less than a tenth as much. It was a huge success and sold 50 units. The successor to the PDP-8 came in 1965 became an even bigger success and sold 50.000 units.
Integrated Circuits
The next major advances came in 1958, when Robert Noyce invented the integrated circuit, which permitted more efficient miniaturization. This era, which lasted until the early 1980s was dominated by the IBM System 360, the first standardized computer series with machines in different performance classes. While DEC's created PDP-11 series, which was very successful, slightly less powerful and much cheaper than similar IBM model.
VLSI and IBM PCs
Integration trend continued and at the beginning of the 1980s had reached what is known as VLSI (Very Large Scale Integration, "very large scale integration") with millions of transistors on an integrated circuit board. This meant that computers were getting small enough to be used privately and this gave rise to the trend of home computer. In 1977 Commodore released an 8-bit computer (PET) and about the same time Apple released the Apple II. In 1981 International Business Machine produced IBM personal computer which is call IBM PC with an open standard for plug-in card and other components. A few weeks before release, however, another PC named Sirius I was also released, which was created by Chuck Peddle. IBM PC is the computer that became known and soon started to emerge an industry for making what it called the IBM PC-compatible personal computers. 1984 showed that one competitor from Apple (Macintosh, 128k) which had one of those days very easy to use graphical interface that still has many similarities with modern operating systems.
PC or Personal Computer
The term comes from the English PC Personal Computer, "PC". The term has been used in full in the 1960s, but the acronym became known as IBM registered and marketed the brand IBM PC. The specification for this early home computers were published openly, and IBM PC-compatible computers became common. These often came to be known only for PC, so that the term now often refers to any kind of computer whose parts are compatible with other PCs. A rival group is known as the Mac family, which is marketed by Apple Inc. Meanwhile, the broader significance PCs maintained in parallel.
Computer Components
Components of a modern personal computer: (1) monitor, (2) motherboards, (3) CPU, (4) ATA ports, (5) memory, (6), plug-in card, (7) power supply, (8) CDs or DVDs, (9) hard drive, (10) and keyboard (11) mouse.
Although computers technology has changed dramatically since the early 1940's, as used in most cases is still the basic structure was first proposed by John von Neumann in the 1940s. Von Neumann architecture divides the computer into four main sections: the arithmetic unit, control unit, memory and various input / output devices (I/O devices). Arithmetic units and the controller are now often integrated in a chip processor and is called after the English shortened CPU Central Processing Unit.
Types of Computers
There are several types of design of personal computers, such as tower, desktop computer, laptop and PDA. Tower model is most common, and is designed for the computer to stand upright. The traditional desktop computer is less common today. It is usually slightly smaller in size and is designed to provide the bottom of the screen placed on top, but could in itself well be on edge. The difference is more about how you want to see their workplace. Laptop model, the portable computer, is constructed of a plate, including processor, hard drive, working memory, keyboard, etc.. and another plate with a screen - these panels folded against one another during transport. It is intended to be held in your lap when you sit down. Palmtop is a handheld computer - often integrated in a mobile phone.
Mainframes are available in several styles, from the individual computers that can resemble a small personal computer to the really big and can fill a room. A server can be described as something between a mainframe and a PC without a monitor, mouse and keyboard. Often, a server in a standard format that permits many assembled together in one stand (sometimes housed in a cabinet). There are also smaller computers that are often more specialized, such as bike computers and flight computers.
Memory
The memory consists of a sequence of cells, each one housing a small piece of information. The information can either be the data processing or computer instructions, parts of the program, that tells the computer what to do. The blurry line between data and programs are an important part of the Von Neuman architecture. The size of each memory cell and the number of such cells naturally vary from computer to computer. Memory size is usually measured in bytes unit. The amount of memory in a PC today is measured in how much working memory it contains. The year 2006 is a normal amount of memory between 256 and 4096 megabytes (MB). It is important to distinguish between working memory and storage memory. Working memory is the fastest, but emptied the power is turned off. Storage memory is the memory where programs and data stored long-term. Nowadays, hard drives, flash drives and CD-ROM/DVD discs most common storage memories.
Arithmetic Logic Unit
This part of the computer performs arithmetic and logic operations. By adding two numbers, or invert a speech.
Controller
Controller is the computer connection, a control unit, especially on the part of a computer system that controls the interpretation of instructions and data transmission from main memory to the various units and vice versa. There are controller including USB, hard drive, floppy drive and graphics.
I / O devices
I / O stands for English input / output. Input devices that allow data retrieved from the outside world, and output devices means that the results are presented in an appropriate manner. There is a lot of different types of I / O devices, everything from keyboards, monitors, printers and floppy disks for webcams.
Computer Programs
The computer program is a long list of instructions the computer carries out in turn. Some instructions, called programs hope, instructs the computer to continue the process with a different instruction than the one immediately succeeding. Those can be conditional so that the program only hope is lost if a certain condition is met. This allows the computer to make decisions and to perform various actions, depending on the result of a calculation or due to another condition. Many programs contain millions of instructions and the instructions are usually performed repeatedly. A typical modern PC (2003) can carry between two and three billion such instructions per second. Programs can be written in different so-called programming languages such as C + +, Java and Pascal. For the computer to understand the instructions are translated to the program usually known as machine code with a compiler.
A computer may seem to run multiple applications simultaneously. This is usually with an English word is called multitasking. In fact, the controller jumps with short intervals between programs in different parts of the memory in such a way that it gives the impression that it goes together. Your computer's operating system is the software that makes sure that all this is that it is intended. The operating system also includes software code that exploited a lot of their regular programs, such as drivers to help with the details of how to control and communicate with all I / O devices. Another example of built-in utilities are the math coprocessor, which is specially designed to rapidly perform mathematical calculations such as trigonometric functions, logarithms and so on.
When you buy a computer it also usually follows with a series of utility programs with the operating system. For example, the Web browser, word processor, calculator and more. Also entertainment programs such as movie and music player or computer games can follow.
<pre> Adapted from Wikipedia </pre>
About Computer
A computer is a PC or a computer which can do automatic calculations. Another older words workstation, a computer, which solves one or more specialized tasks. Today it has become obsolete, but still used on freestanding powerful computers, for example. used for versatility calculations.
The idea of program controlled calculators has roots back to the industrial breakthrough in England around 1800. The clear example. by Jacquard mønstervæv and Charles Babbage development. Punch card machines were also programmable. Hollerith / IBM's machines were programmed with switching boards, while Powers took connection box.
In the late 1920s came the first computer science. They played no great quantitative role but was important for the continued technical development. There was no analytical statistics and compilation of astronomical tables. Then came a host of other tasks. These demands for machines with growing programs. Connectionbox'enes rigidity made them unsuitable for this purpose and all scientific calculations were performed on clutch Plate programmed machines.
ENIAC, America's first computer.
The first computers were built in Germany, England and the United States between 1940 and 1950 (eg. Z3, ENIAC, Colossus), but their history goes back to the calculator projects in 1930 were developed in various research settings. During the Second World War was a series calculator projects in England, Russia and the United States considered important war and therefore state-funded. After the war, continued public funding of scientific research and development, and initiation of the cold war put additional focus on the development of computers for military purposes, for example. SAGE to monitor U.S. airspace, a development which was reinforced after the outbreak of the Korean War.
Parallel to the military research began from the early 1950s in Germany, England and particularly the U.S. development of computers on a commercial basis, both for sale to research (Z4, UNIVAC I, IBM 701, Ferranti Mark I) and for use in private companies (IBM 650, IBM 704). Towards the late 1950s launched a wide range of business computers, and the industry gradually came to dominate the development of the machines, while research is focused on applications and software.
During this period batch driving the all-dominant way to use computers and the widespread view was that it was most effective with few, very large computers used for running programs one by one. Interactive use of computers were found only in a few specialized military applications and in a few research settings (eg. Lincoln Lab, where the TX-0 and TX-2 was developed for interactive use).
About Computer
A computer is a machine that processes data, information that it receives from users or programs. If you go down and look at the CPU, it consists only of 0 - and 1-metals (Bits). It basically consists of: input device, the Danish one input device or different input device, a processing unit, the processor (CPU) with memory (RAM) to store data temporarily during the processing of them, a hard disk for storing the operating system, applications and data f . as documents after the computer is off, and a device for displaying results (for example. be a screen or a printer).
Computers can be divided into two main areas:
Personal computers (usually only a single display cabinet containing the CPU - processing unit, memory, hard disk, and input (receive info from the outside) and output (send info to, for example. Screen, printer, hard drive, burn CD, etc.).
Large computer systems (for handling large amounts of data in companies / organizations). This also includes server and mainframe).
Large computer systems
The large computer systems has great memory and rapid calculation units processors. Here processed information that would take a long time on a personal computer.
Another important difference is that the servers and especially mainframes are designed to be accessible at all times. This means among other things, hardware and software can be upgraded while the system is running. There will also often be redundant components such as the power system installed in the machine.
The idea of program controlled calculators has roots back to the industrial breakthrough in England around 1800. The clear example. by Jacquard mønstervæv and Charles Babbage development. Punch card machines were also programmable. Hollerith / IBM's machines were programmed with switching boards, while Powers took connection box.
In the late 1920s came the first computer science. They played no great quantitative role but was important for the continued technical development. There was no analytical statistics and compilation of astronomical tables. Then came a host of other tasks. These demands for machines with growing programs. Connectionbox'enes rigidity made them unsuitable for this purpose and all scientific calculations were performed on clutch Plate programmed machines.
ENIAC, America's first computer.
The first computers were built in Germany, England and the United States between 1940 and 1950 (eg. Z3, ENIAC, Colossus), but their history goes back to the calculator projects in 1930 were developed in various research settings. During the Second World War was a series calculator projects in England, Russia and the United States considered important war and therefore state-funded. After the war, continued public funding of scientific research and development, and initiation of the cold war put additional focus on the development of computers for military purposes, for example. SAGE to monitor U.S. airspace, a development which was reinforced after the outbreak of the Korean War.
Parallel to the military research began from the early 1950s in Germany, England and particularly the U.S. development of computers on a commercial basis, both for sale to research (Z4, UNIVAC I, IBM 701, Ferranti Mark I) and for use in private companies (IBM 650, IBM 704). Towards the late 1950s launched a wide range of business computers, and the industry gradually came to dominate the development of the machines, while research is focused on applications and software.
During this period batch driving the all-dominant way to use computers and the widespread view was that it was most effective with few, very large computers used for running programs one by one. Interactive use of computers were found only in a few specialized military applications and in a few research settings (eg. Lincoln Lab, where the TX-0 and TX-2 was developed for interactive use).
About Computer
A computer is a machine that processes data, information that it receives from users or programs. If you go down and look at the CPU, it consists only of 0 - and 1-metals (Bits). It basically consists of: input device, the Danish one input device or different input device, a processing unit, the processor (CPU) with memory (RAM) to store data temporarily during the processing of them, a hard disk for storing the operating system, applications and data f . as documents after the computer is off, and a device for displaying results (for example. be a screen or a printer).
Computers can be divided into two main areas:
Personal computers (usually only a single display cabinet containing the CPU - processing unit, memory, hard disk, and input (receive info from the outside) and output (send info to, for example. Screen, printer, hard drive, burn CD, etc.).
Large computer systems (for handling large amounts of data in companies / organizations). This also includes server and mainframe).
Large computer systems
The large computer systems has great memory and rapid calculation units processors. Here processed information that would take a long time on a personal computer.
Another important difference is that the servers and especially mainframes are designed to be accessible at all times. This means among other things, hardware and software can be upgraded while the system is running. There will also often be redundant components such as the power system installed in the machine.
Personal Computer
A computer as PC (Personal Computer) is an electronic machine that receives and processes data into useful information. A computer is a collection of integrated circuits and related components that can execute data with accuracy, speed and as indicated by a user or automatically by another program.
A variety of sequences of instructions or routines that are ordered, organized and systematized according to a wide range of practical applications and precisely determined, a process which has been called by the name of programming and performing it is called a programmer, the computer, with the application or software, and supplied with data which is known as "input", and required time of execution, to provide the end product of data processing, which is called "output."
The information can then be used, reinterpreted, copied, transferred, or relayed to others, computers, components, locally or remotely using various telecommunication systems and can be recorded , saved or stored on any device or storage unit.
The main feature that distinguishes it from other similar devices, such as non-programmable calculator is that it is a general purpose machine, can perform many different tasks, based on the possibilities offered by programming languages and hardware.
Architecture
Although the technologies used in computers have changed a lot since the first models appeared in the 40s, most still use the von Neumann architecture, published in the early 1940s by John von Neumann, that other authors attributed to John Eckert and John William Mauchly.
Von Neumann architecture describes a computer with four main sections: the arithmetic logic unit (ALU: Arithmetic Logic Unit), the control unit, main memory, and input devices and output (I/O). These parts are interconnected by channels called buses drivers.
Memory is a sequence of numbered storage cells, where each one is a bit or piece of information. The statement is the information needed to make what you want with the computer. The "cells" contain data needed to carry out the instructions in the computer. The number of cells vary widely from computer to computer, and the technologies used for memory have changed considerably, ranging from electromechanical relays, mercury-filled tubes in which acoustic pulses were formed, arrays of permanent magnets, individual transistors to circuits integrated with millions of cells in a single chip. In general, memory can be rewritten several million times (RAM), is more like a slate tablet to a memory (ROM) that can only be written once.
The processor (also called central processing unit or CPU) consists of: A typical schematic symbol for an ALU: A and B are operands; R is the output, F is the input of the control unit, D is a state of the output.
The arithmetic logic unit or ALU is a device designed and built to perform basic operations such as arithmetic operations (addition, subtraction, ...), logical operators (AND, OR, NOT) and comparison or relational operations. This unit is where does all the work computer.
The control unit is in the direction of the locations in memory containing the instruction that
the computer will perform at the time, retrieves the information by putting it in the ALU for the operation to be developed. Then transfers the result to appropriate locations in memory. Once the above occurs, the control unit goes to the next instruction (typically located at the following location, unless the instruction is a jump instruction informing the computer that the next instruction is located in another position memory).
Devices E / S used the computer to obtain information from the outside world and / or communicate the results generated by the computer to the outside. There is a very wide range of devices E / S as keyboards, monitors, floppy drives and webcams.
Desktop Computer: Peripheral and auxiliary devices
Monitor
The monitor or computer screen is an output device through an interface, shows the results of processing a computer. There are three main types of monitors: the cathode ray tube (or CRT), the plasma display (PDP) and LCD display (or LCD).
Keyboard
A keyboard is a peripheral, physical or virtual (eg on-screen keyboards or keypads laser), used for entering commands and data into a computer. It originates from the teletype and electric typewriters, which were used as keyboards of the first computers and storage devices (tape recorders, paper and punch cards). Although physically there are a myriad of shapes, are usually classified primarily by the distribution of alpha-numeric keyboard in your area, except for very special cases it is common to all devices and manufacturers (including Arabs and Japanese keyboard).
Mouse
The mouse is a computer peripheral in the hand, usually made of plastic, used as input data or control. Used with one of the two hands of the user and detects the relative movement in two dimensions on the horizontal surface on which it rests, usually reflected by a pointer or arrow on the monitor. Previously, the displacement information was transmitted by the movement of a ball under the mouse, which drove two rollers that correspond to the axes X and Y. Today, the pointer reacts to movements due to a beam of light reflected between the mouse and the surface on which it is located. It should be noted that an optical mouse resting on a mirror for example is unusable, because the laser light does not play its proper role. The surface to support the mouse should be opaque, a surface that does not generate a reflection.
Printer
A printer is a computer peripheral that allows you to produce a permanent copy text or graphics of documents stored in electronic format, printing on gloss paper data on physical media, usually on paper or transparencies, using ink or laser technology. Many printers are used as peripherals, and are attached to the computer by a cable. Some printers, commonly known as network printers have a network interface (typically wireless or Ethernet), and can serve as a device to print on any documents to any network user. There are also multifunction printers that aside from his duties as printer copier and scanner work.
Computer Scanner
In computers, a scanner is a peripheral that is used to convert, through the use of light, or any other printed images to digital format.
Hard Drive
The hard disk is a digital magnetic recording system, is where in most cases the operating system resides on the computer. In the hard disks are stored user data. In it we find within the housing a series of stacked metal plates spinning at high speed. These dishes are placed on the heads in charge of reading or writing magnetic impulses. In a new generation are the solid-state hard drives, which carry the principle of USB memory sticks.
Speakers
The speakers are used to hearing the sounds emitted by the computer, such as music, sound errors, conferences. Usually the speakers are built into the computer. In laptops, the majority of cases, are integrated in a manner not seen. And in the over-table are in the monitor, but the tower also carries sounds to indicate an error.
Other concepts and curiosities
Some larger computers differ from the previous model in one important respect, because they have multiple CPUs and control units working simultaneously. Furthermore, some computers, used primarily for research, are very different from the previous model, but do not have many commercial applications.
Today you can get the impression that computers are running several programs simultaneously. This is called multitasking, and is more common to use the second term. In fact, the CPU executes instructions of a program and then after a short period of time, switch to a second program and executes some of his instructions. This creates the illusion that they are running multiple programs simultaneously, dividing CPU time between programs. This is similar to the film that is formed by a rapid succession of frames. The operating system is the program that usually controls the allocation of time.
The operating system is a kind of tool box full of routines. Every time a computer routine is used in many different types of programs over many years, programmers will the operating system routine at the end.
The operating system used to decide, for example, which programs are running, and when, and what sources (device memory or I / S) are used. The operating system has other functions that offer other programs, such as codes that serve programmers write programs for a machine without knowing the internal details of all electronic devices connected.
Today they are starting to include some programs the operating system widely used, because this is an inexpensive way to distribute them. Not surprisingly, an operating system including Internet browsers, word processors, email programs, network interfaces, movie players and other programs that previously had to obtain and install separately.
The first digital computers of large size and cost, were used primarily for scientific calculations. ENIAC, one of the first computers, estimated densities of neutron cross to see if they explode the hydrogen bomb. CSIR Mk I, the first Australian computer, evaluated rainfall patterns for a large hydropower project. The early visionaries predicted that the program would play chess, watch movies and other uses.
The people working for governments and companies also used the computers to automate many of the tasks of collecting and processing data, which were once made by humans, such as maintaining and updating accounting and inventory. In the academic world, scientists in all fields began to use computers to do their own analysis. The continuing decline in prices of computers allowed the use of increasingly smaller companies. Businesses, organizations and governments are beginning to employ a large number of small computers to perform tasks previously done by large, expensive mainframes. The meeting of several small computers in one place called tower servers.
With the invention of the microprocessor in 1970, it was possible to manufacture very cheap computers. Personal computers became famous for carrying out various tasks as keeping books, writing and printing documents. Calculate probabilities and other repetitive mathematical tasks with spreadsheets, communicating via email and the Internet. However, the widespread availability of computers and their easy adaptation to the needs of each person, have used for several purposes.
At the same time, small computers are almost always with a fixed schedule, they began to make its way between applications from home, cars, aircraft and industrial machinery. These embedded processors controlling the behavior of the devices more easily, enabling the development of more complex control functions such as antilock braking systems in cars. In the early 21st century, most appliances, almost all types of electrical transport and most of the production lines of factories run on a computer. Most engineers think that trend will continue.
Currently, personal computers are used both for research and for entertainment (video games), but still large computers used for complex mathematical calculations and other uses of science, technology, astronomy, medicine, etc..
Perhaps the most interesting "descendant" of the crossing between the concept of the PC or personal computer and the so-called supercomputers is the Workstation or workstation. This term, originally used for equipment and recording machines, digital recording and audio processing, and now used specifically in reference to workstations (literally translated from English) is used to name computers, mainly due to utility specially dedicated to scientific computing tasks, efficiency against the clock and user accessibility in programs and professional and special software, can perform the jobs of a large number of calculations and "force" operation. A Workstation is, in essence, a team oriented individual work, with high capacity and performance calculation than the conventional PCs, which are still high cost components, due to its design focused on the election and synergistic combination components. In these cases, the software design is the foundation of the team, claiming, along with user requirements, the final design of the Workstation.
Etymology of the word computer
The Spanish word comes from the French computer ordinateur, referring to the God who brings order to the world ("Dieu qui met de l'ordre dans le monde"). In part because of marketing issues, since the description given by IBM for introduction in France in 1954 placed the performance capabilities of the machine near omnipotence, misconception that exists today to consider that the universal Turing machine is capable of computing absolute todo. In 1984, French recognized scholars, in the debate, "Les jeunes, the technique et nous", the use of this noun is wrong, because the function of a computer is processing data, not to órdenes. While others, like the professor of Latin philology Jacques Perret knowledgeable about the religious origin of the term, he is considered more correct than the alternativas1.
The use of the word ordinateur has been exported to some languages of the Iberian peninsula, as the Aragonese, Castilian, Catalan and Euskera. The Spanish spoken in Latin America and other European languages, like Portuguese, German and the Netherlands, used the term derived computare.
A variety of sequences of instructions or routines that are ordered, organized and systematized according to a wide range of practical applications and precisely determined, a process which has been called by the name of programming and performing it is called a programmer, the computer, with the application or software, and supplied with data which is known as "input", and required time of execution, to provide the end product of data processing, which is called "output."
The information can then be used, reinterpreted, copied, transferred, or relayed to others, computers, components, locally or remotely using various telecommunication systems and can be recorded , saved or stored on any device or storage unit.
The main feature that distinguishes it from other similar devices, such as non-programmable calculator is that it is a general purpose machine, can perform many different tasks, based on the possibilities offered by programming languages and hardware.
Architecture
Although the technologies used in computers have changed a lot since the first models appeared in the 40s, most still use the von Neumann architecture, published in the early 1940s by John von Neumann, that other authors attributed to John Eckert and John William Mauchly.
Von Neumann architecture describes a computer with four main sections: the arithmetic logic unit (ALU: Arithmetic Logic Unit), the control unit, main memory, and input devices and output (I/O). These parts are interconnected by channels called buses drivers.
Memory is a sequence of numbered storage cells, where each one is a bit or piece of information. The statement is the information needed to make what you want with the computer. The "cells" contain data needed to carry out the instructions in the computer. The number of cells vary widely from computer to computer, and the technologies used for memory have changed considerably, ranging from electromechanical relays, mercury-filled tubes in which acoustic pulses were formed, arrays of permanent magnets, individual transistors to circuits integrated with millions of cells in a single chip. In general, memory can be rewritten several million times (RAM), is more like a slate tablet to a memory (ROM) that can only be written once.
The processor (also called central processing unit or CPU) consists of: A typical schematic symbol for an ALU: A and B are operands; R is the output, F is the input of the control unit, D is a state of the output.
The arithmetic logic unit or ALU is a device designed and built to perform basic operations such as arithmetic operations (addition, subtraction, ...), logical operators (AND, OR, NOT) and comparison or relational operations. This unit is where does all the work computer.
The control unit is in the direction of the locations in memory containing the instruction that
the computer will perform at the time, retrieves the information by putting it in the ALU for the operation to be developed. Then transfers the result to appropriate locations in memory. Once the above occurs, the control unit goes to the next instruction (typically located at the following location, unless the instruction is a jump instruction informing the computer that the next instruction is located in another position memory).
Devices E / S used the computer to obtain information from the outside world and / or communicate the results generated by the computer to the outside. There is a very wide range of devices E / S as keyboards, monitors, floppy drives and webcams.
Desktop Computer: Peripheral and auxiliary devices
Monitor
The monitor or computer screen is an output device through an interface, shows the results of processing a computer. There are three main types of monitors: the cathode ray tube (or CRT), the plasma display (PDP) and LCD display (or LCD).
Keyboard
A keyboard is a peripheral, physical or virtual (eg on-screen keyboards or keypads laser), used for entering commands and data into a computer. It originates from the teletype and electric typewriters, which were used as keyboards of the first computers and storage devices (tape recorders, paper and punch cards). Although physically there are a myriad of shapes, are usually classified primarily by the distribution of alpha-numeric keyboard in your area, except for very special cases it is common to all devices and manufacturers (including Arabs and Japanese keyboard).
Mouse
The mouse is a computer peripheral in the hand, usually made of plastic, used as input data or control. Used with one of the two hands of the user and detects the relative movement in two dimensions on the horizontal surface on which it rests, usually reflected by a pointer or arrow on the monitor. Previously, the displacement information was transmitted by the movement of a ball under the mouse, which drove two rollers that correspond to the axes X and Y. Today, the pointer reacts to movements due to a beam of light reflected between the mouse and the surface on which it is located. It should be noted that an optical mouse resting on a mirror for example is unusable, because the laser light does not play its proper role. The surface to support the mouse should be opaque, a surface that does not generate a reflection.
Printer
A printer is a computer peripheral that allows you to produce a permanent copy text or graphics of documents stored in electronic format, printing on gloss paper data on physical media, usually on paper or transparencies, using ink or laser technology. Many printers are used as peripherals, and are attached to the computer by a cable. Some printers, commonly known as network printers have a network interface (typically wireless or Ethernet), and can serve as a device to print on any documents to any network user. There are also multifunction printers that aside from his duties as printer copier and scanner work.
Computer Scanner
In computers, a scanner is a peripheral that is used to convert, through the use of light, or any other printed images to digital format.
Hard Drive
The hard disk is a digital magnetic recording system, is where in most cases the operating system resides on the computer. In the hard disks are stored user data. In it we find within the housing a series of stacked metal plates spinning at high speed. These dishes are placed on the heads in charge of reading or writing magnetic impulses. In a new generation are the solid-state hard drives, which carry the principle of USB memory sticks.
Speakers
The speakers are used to hearing the sounds emitted by the computer, such as music, sound errors, conferences. Usually the speakers are built into the computer. In laptops, the majority of cases, are integrated in a manner not seen. And in the over-table are in the monitor, but the tower also carries sounds to indicate an error.
Other concepts and curiosities
Some larger computers differ from the previous model in one important respect, because they have multiple CPUs and control units working simultaneously. Furthermore, some computers, used primarily for research, are very different from the previous model, but do not have many commercial applications.
Today you can get the impression that computers are running several programs simultaneously. This is called multitasking, and is more common to use the second term. In fact, the CPU executes instructions of a program and then after a short period of time, switch to a second program and executes some of his instructions. This creates the illusion that they are running multiple programs simultaneously, dividing CPU time between programs. This is similar to the film that is formed by a rapid succession of frames. The operating system is the program that usually controls the allocation of time.
The operating system is a kind of tool box full of routines. Every time a computer routine is used in many different types of programs over many years, programmers will the operating system routine at the end.
The operating system used to decide, for example, which programs are running, and when, and what sources (device memory or I / S) are used. The operating system has other functions that offer other programs, such as codes that serve programmers write programs for a machine without knowing the internal details of all electronic devices connected.
Today they are starting to include some programs the operating system widely used, because this is an inexpensive way to distribute them. Not surprisingly, an operating system including Internet browsers, word processors, email programs, network interfaces, movie players and other programs that previously had to obtain and install separately.
The first digital computers of large size and cost, were used primarily for scientific calculations. ENIAC, one of the first computers, estimated densities of neutron cross to see if they explode the hydrogen bomb. CSIR Mk I, the first Australian computer, evaluated rainfall patterns for a large hydropower project. The early visionaries predicted that the program would play chess, watch movies and other uses.
The people working for governments and companies also used the computers to automate many of the tasks of collecting and processing data, which were once made by humans, such as maintaining and updating accounting and inventory. In the academic world, scientists in all fields began to use computers to do their own analysis. The continuing decline in prices of computers allowed the use of increasingly smaller companies. Businesses, organizations and governments are beginning to employ a large number of small computers to perform tasks previously done by large, expensive mainframes. The meeting of several small computers in one place called tower servers.
With the invention of the microprocessor in 1970, it was possible to manufacture very cheap computers. Personal computers became famous for carrying out various tasks as keeping books, writing and printing documents. Calculate probabilities and other repetitive mathematical tasks with spreadsheets, communicating via email and the Internet. However, the widespread availability of computers and their easy adaptation to the needs of each person, have used for several purposes.
At the same time, small computers are almost always with a fixed schedule, they began to make its way between applications from home, cars, aircraft and industrial machinery. These embedded processors controlling the behavior of the devices more easily, enabling the development of more complex control functions such as antilock braking systems in cars. In the early 21st century, most appliances, almost all types of electrical transport and most of the production lines of factories run on a computer. Most engineers think that trend will continue.
Currently, personal computers are used both for research and for entertainment (video games), but still large computers used for complex mathematical calculations and other uses of science, technology, astronomy, medicine, etc..
Perhaps the most interesting "descendant" of the crossing between the concept of the PC or personal computer and the so-called supercomputers is the Workstation or workstation. This term, originally used for equipment and recording machines, digital recording and audio processing, and now used specifically in reference to workstations (literally translated from English) is used to name computers, mainly due to utility specially dedicated to scientific computing tasks, efficiency against the clock and user accessibility in programs and professional and special software, can perform the jobs of a large number of calculations and "force" operation. A Workstation is, in essence, a team oriented individual work, with high capacity and performance calculation than the conventional PCs, which are still high cost components, due to its design focused on the election and synergistic combination components. In these cases, the software design is the foundation of the team, claiming, along with user requirements, the final design of the Workstation.
Etymology of the word computer
The Spanish word comes from the French computer ordinateur, referring to the God who brings order to the world ("Dieu qui met de l'ordre dans le monde"). In part because of marketing issues, since the description given by IBM for introduction in France in 1954 placed the performance capabilities of the machine near omnipotence, misconception that exists today to consider that the universal Turing machine is capable of computing absolute todo. In 1984, French recognized scholars, in the debate, "Les jeunes, the technique et nous", the use of this noun is wrong, because the function of a computer is processing data, not to órdenes. While others, like the professor of Latin philology Jacques Perret knowledgeable about the religious origin of the term, he is considered more correct than the alternativas1.
The use of the word ordinateur has been exported to some languages of the Iberian peninsula, as the Aragonese, Castilian, Catalan and Euskera. The Spanish spoken in Latin America and other European languages, like Portuguese, German and the Netherlands, used the term derived computare.
Computer
A computer is a machine with a processor unit that have the ability to execute and store programs. Computer is an electronic circuit that manipulate data in binary form, or bits. This machine can automatically process data or information, according to predefined sequences of instructions, also called programs.
Computer interacts with the environment through devices like the monitor, keyboard, mouse, printer, modem, CD. The computers can be classified according to several criterias (scope, size or architecture).
History of Computing.
In 1936, the publication of the seminal paper of computer science in On Computable Numbers with Application to the Entscheidungsproblem (pdf) year by Alan Turing would kick off the creation of the programmable computer. He presents the Turing machine, the first universal programmable computer, and invented the concepts of programming and program.
Turing published a text of 35 pages where he designed an imaginary machine that can perform any calculation from a binary 0 and 1. He says this will help implement a program unlimited calculations. He suggested that this machine could be real and could be programmed to work at 0 and 1.
The result of the problems addressed is impossible to distinguish the results of a human brain. It was the birth of artificial intelligence, because the calculation is the same, regardless of the object, machine or man, who does. Calculation is a function that is understood by both man and machine. The fact that an operation is simulated by a machine, it is similar to the mechanism, but what changes, what are the mechanisms of "computation" (computer).
Von Neumann opposed Skinner at a seminar on the theme: brain mechanisms in behavior. It is the first to use the word "cybernetics" (comes from "steering" the brain governs, refers to the science of any system capable of self-regulation and communication, as humans). Skinner wants to restore behaviorism. Von Neumann wants to design a program recorded and programmed into the machine: the birth of the first computer. In 1951, organized in Paris by the CNRS, the Conference of the computing machine: the birth of cognitive psychology conceived as computation.
Shortly before the Second World War, came the first electromechanical calculators, built according to the ideas of Alan Turing. The machines were quickly supplanted by the first electronic computers, much more efficient.
The first computer operating in binary language was the Colossus, developed during the Second World War, it was not complete. Turing had worked well in the project. At the end of the war, it was dismantled and hidden due to its strategic importance. ENIAC, commissioned in 1946, the first fully electronic computer completely build based on Turing theory.
The word computer was introduced by IBM France in 1955. Francois Girard, then head of advertising department of the company, had the idea to consult with his former professor of literature in Paris, Jacques Perret, to ask him to suggest a word that characterizes the best what is commonly called a computer.
.
The first multi tasks computer is the Bull Gamma 60 in 1958. The first portable computer is ZX-81 Sinclair, it was sold in kit and had a memory of 1 KB (one kilobyte, 1024 bytes), then come the extension that enabled him to reach 16K , then appeared familly oriented computers like the Apple II in 1977, the Hector in 1981, the Commodore 64 in 1982, Oric-1 in 1983, Apple IIe, then the Amstrad 464.664 6128 ...
Simple Computing
The computers were first used for calculation (integer first, then floating). However, we can categorize them as simple computers: in fact the result of processing a computer can not only be a series of numbers, but also a new program (used by the computer or another). In Von Neumann architecture, data is normalized and can be interpreted either as numbers, instructions, logical values or arbitrarily defined symbol (letter of the alphabet, for example).
The calculation is one of possible applications. In this case, the data are treated as numbers.
The computer is used also for its ability to organize information, among other magnetic storage devices. This ability to organize information has generalized the use of word processing by the general public.Management of relational databases can also retrieve and consolidate distributed information seen by the user as several independent tables.
This creation of a neologism was the cause of multiple translations of expressions Supercomputer or quantum computer. In the latter case, the use of the word "computer" is just overrated because the possibilities to quantum computing are far from the versatility of a "computer".
Experience has learned to distinguish two aspects in a computer, the second of which had been initially underestimated the physical architecture, hardware (aka hardware or hard); software architecture (aka software or software), a computer very technically advanced for its time as the Gamma 60 the company Bull was not as successful as expected, for the simple reason that there was little capacity to implement conveniently its technical possibilities. The software - and its complement services (training, maintenance, ...) - form since the mid-1980s most of the costs of computer equipment, hardware there being a minority.
The computers may be susceptible to EMI bombs.
How a computer Work
Of all the machines invented by humans, the computer is one that is closest to the anthropological concept following:
Body entry. Body of information processing. Body Release
In humans, the organs of entry are the five senses, body treatment is the brain whose software is learning with constant updates during its lifetime, then the output devices are the muscles. For modern computers, the organs of entry are the keyboard and mouse and output devices, screen, printer, DVD burner, etc..
Advanced Computer
The techniques used to manufacture these machines have changed enormously since the 1940s and have become a technology (that is to say, organized around an industrial techniques) full since the 1970s. Many still use the concepts defined by John von Neumann, although this architecture is in decline: the programs do not change over themselves (which would be considered bad programming practice), and the material takes into account this new gives between now significantly storing instructions and data, including the caches.
The architecture of von Neumann's computer broke down into four distinct parts:
the arithmetic logic unit (ALU) or processing unit: its role is to perform basic operations, one much like a calculator;
control unit. This is equivalent to fingers actuating the calculator;
memory that contains both data and program that will tell the control unit to the calculations on that data. The memory is divided into RAM (programs and data during operation) and memory (programs and data base of the machine);
Input-Output: devices that can communicate with the outside world.
UAL and UA
The arithmetic logic unit or ALU is the element that performs the basic operations (addition, subtraction ...), logical operators (AND, OR, NOR, etc..) And comparison operations (for example the comparison of tie between two areas of memory). Is that the ALU performs the calculations of the computer.
The control unit takes its instructions in memory. They tell him what she should order the UAL
and how it may have to act according to the results that it will provide. Once finished, the control unit is going to the following statement or to another statement in which he directs the program to connect.
The control unit facilitates communication between the arithmetic and logic unit, memory and peripherals. It supports most of the execution of instructions in the computer.
Memory
Within the system, the memory can be described as a series of numbered cells, each containing a small amount of information. This information can be used to tell the computer what to do (instructions) or contain data to be processed. In most architectures, it is the same memory that is used for both functions. In massively parallel computers, it even admits that the program instructions are substituted for others during the operation when it results in greater efficiency. This practice was once common, but the requirements of readability of software engineering have been declining, except in this particular case, for several decades.
This memory can be rewritten as many times as necessary. The size of each block of memory and the technology used varied depending on the costs and requirements: 8 bits for telecommunications, 12-bit for instrumentation (DCS) and 60 bits for big scientific computers (Control Data). A consensus was eventually found around byte addressable as a unit and instructions on size 4 or 8 bytes.
In all cases, the byte is addressable, which simplifies writing programs.
The techniques used to make submissions have included electromechanical relays, mercury tubes in which acoustic waves were generated, individual transistors, ferrite toroids and finally integrated circuits include millions of transistors.
Input-Output
The device input / output enables the computer to communicate with the outside. These devices are very important, the keyboard on the screen.
The common point between all input devices is that they convert the information they retrieve from the external data understandable by the computer. Conversely, output devices decode the information provided by the computer to make it understandable by the user.
Computer Bus
These parts are connected by three buses, the address bus, data bus and control bus. A bus is a grouping of a number of electrical conducting a son to carry on the binary information encoded on several bits.
The address bus carries the addresses generated by the CPU (Central Processing Unit) to select a memory cell or an internal register of one of the blocks. The number of bits conveyed by this bus depends on the amount of memory that must be addressed.
The data bus carries data between the various elements of the system.
The control bus carries the different timing signals needed for operating the system: read signal (RD), write signal (WR), select signal (CS: Chip Select).
Architecture
Miniaturization can integrate UAL and control unit within a single integrated circuit known as the microprocessor.
Typically, the memory is located on integrated circuits near the CPU, a part of this memory, the cache can be located on the same integrated circuit as the UAL.
The whole is, on most architectures, complete with a clock speed processor. Of course, we want it to be as fast as possible, but we can not increase his speed without limits for two reasons:
More clock is faster and the processor generates heat (as the square of the frequency). Excessive temperatures may damage the processor; there is a pace where the CPU becomes unstable and it generates errors that most often lead to a crash.
The trend was from 2004 to consolidate several LGUs in the same processor or multiple processors in the same chip. Indeed, the progressive miniaturization (see Moore's Law) permits with little change in cost. Another trend, since 2006, ARM, is to microprocessors without clock: half of the heat dissipation effect is due to clock signals when the microprocessor works, again, without a microprocessor clock is consuming almost zero when it not work: the only clock signal is then necessary for the refreshment of memories. This advantage is important for portable models.
The main functional difference today compared to the model of Von Neumann is the presence on some architectures of two different caches, one for instructions and one for data (whereas the von Neumann model specified a common memory for both) . The reason for this discrepancy is that the modification by a program's instructions is now considered (except for highly parallel machines) as a practice to be avoided. Therefore, if the cache data must be rewritten in main memory when it is amended, known as the instruction cache will never be, hence simplifying circuits and performance gains.
Instructions
The instructions that the computer can understand are not those of human language. The hardware knows just run a limited number of instructions defined. Typical instructions understood by computers are "copy the contents of cell 123 and placed in cell 456", "add the contents of the cell 321 to cell 654 and place the result in cell 777" and " if the contents of the cell 999 is 0, execute the instruction in cell 345 ". But most of the instructions consist of two zones: one showing what to do, called the opcode, and the other indicating where do we call operand.
Within the computer, the instructions correspond to codes - the code for a copy being for example 001. The set of instructions that a computer supports is called its machine language, language that is a sequence of binary digits, because the instructions and data that is understood by the processor (CPU) consists only of 0 (zero) and 1 (one). 0 = electric current does not pass. 1 = electric current passes.
In general, programmers no longer use such language, but go through what we call a high-level language which is then converted into binary language with a special program (compiler or interpreter as needed). The resulting programs are compiled programs understandable by the computer in his native language.
Some programming languages such as assembler are called low-level languages for the instructions they use are very similar to those of the computer. Programs written in these languages are thus very dependent on the platform for which they were developed. The C language, much easier to read than assembler, thus allows programmers to be more productive. For this reason, we have seen more and more used as material costs fell and hourly wages of programmers increased.
Software
Computer software is a long list of instructions executable by a computer. Many programs contain millions of instructions, made some repeatedly. Nowadays, a personal computer running billions of instructions per second.
Since the mid-1960s, computers running multiple programs simultaneously. This is called multitasking. This applies to all computers today.
In fact, each processor performs a heart program at a time, from one program to another whenever necessary. If the speed of the processor is sufficiently large compared to the number of tasks to perform, the user will feel a simultaneous execution of programs. Priorities for the various programs are generally managed by the operating system.
Operating System
The operating system is the central program that contains the basic programs needed for the proper functioning of computer applications. The operating system allocates physical resources of the computer (CPU, memory ...) with various programs running. It also provides tools to software (such as pilots) to facilitate the use of different devices without having to know the physical details.
Computer interacts with the environment through devices like the monitor, keyboard, mouse, printer, modem, CD. The computers can be classified according to several criterias (scope, size or architecture).
History of Computing.
In 1936, the publication of the seminal paper of computer science in On Computable Numbers with Application to the Entscheidungsproblem (pdf) year by Alan Turing would kick off the creation of the programmable computer. He presents the Turing machine, the first universal programmable computer, and invented the concepts of programming and program.
Turing published a text of 35 pages where he designed an imaginary machine that can perform any calculation from a binary 0 and 1. He says this will help implement a program unlimited calculations. He suggested that this machine could be real and could be programmed to work at 0 and 1.
The result of the problems addressed is impossible to distinguish the results of a human brain. It was the birth of artificial intelligence, because the calculation is the same, regardless of the object, machine or man, who does. Calculation is a function that is understood by both man and machine. The fact that an operation is simulated by a machine, it is similar to the mechanism, but what changes, what are the mechanisms of "computation" (computer).
Von Neumann opposed Skinner at a seminar on the theme: brain mechanisms in behavior. It is the first to use the word "cybernetics" (comes from "steering" the brain governs, refers to the science of any system capable of self-regulation and communication, as humans). Skinner wants to restore behaviorism. Von Neumann wants to design a program recorded and programmed into the machine: the birth of the first computer. In 1951, organized in Paris by the CNRS, the Conference of the computing machine: the birth of cognitive psychology conceived as computation.
Shortly before the Second World War, came the first electromechanical calculators, built according to the ideas of Alan Turing. The machines were quickly supplanted by the first electronic computers, much more efficient.
The first computer operating in binary language was the Colossus, developed during the Second World War, it was not complete. Turing had worked well in the project. At the end of the war, it was dismantled and hidden due to its strategic importance. ENIAC, commissioned in 1946, the first fully electronic computer completely build based on Turing theory.
The word computer was introduced by IBM France in 1955. Francois Girard, then head of advertising department of the company, had the idea to consult with his former professor of literature in Paris, Jacques Perret, to ask him to suggest a word that characterizes the best what is commonly called a computer.
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The first multi tasks computer is the Bull Gamma 60 in 1958. The first portable computer is ZX-81 Sinclair, it was sold in kit and had a memory of 1 KB (one kilobyte, 1024 bytes), then come the extension that enabled him to reach 16K , then appeared familly oriented computers like the Apple II in 1977, the Hector in 1981, the Commodore 64 in 1982, Oric-1 in 1983, Apple IIe, then the Amstrad 464.664 6128 ...
Simple Computing
The computers were first used for calculation (integer first, then floating). However, we can categorize them as simple computers: in fact the result of processing a computer can not only be a series of numbers, but also a new program (used by the computer or another). In Von Neumann architecture, data is normalized and can be interpreted either as numbers, instructions, logical values or arbitrarily defined symbol (letter of the alphabet, for example).
The calculation is one of possible applications. In this case, the data are treated as numbers.
The computer is used also for its ability to organize information, among other magnetic storage devices. This ability to organize information has generalized the use of word processing by the general public.Management of relational databases can also retrieve and consolidate distributed information seen by the user as several independent tables.
This creation of a neologism was the cause of multiple translations of expressions Supercomputer or quantum computer. In the latter case, the use of the word "computer" is just overrated because the possibilities to quantum computing are far from the versatility of a "computer".
Experience has learned to distinguish two aspects in a computer, the second of which had been initially underestimated the physical architecture, hardware (aka hardware or hard); software architecture (aka software or software), a computer very technically advanced for its time as the Gamma 60 the company Bull was not as successful as expected, for the simple reason that there was little capacity to implement conveniently its technical possibilities. The software - and its complement services (training, maintenance, ...) - form since the mid-1980s most of the costs of computer equipment, hardware there being a minority.
The computers may be susceptible to EMI bombs.
How a computer Work
Of all the machines invented by humans, the computer is one that is closest to the anthropological concept following:
Body entry. Body of information processing. Body Release
In humans, the organs of entry are the five senses, body treatment is the brain whose software is learning with constant updates during its lifetime, then the output devices are the muscles. For modern computers, the organs of entry are the keyboard and mouse and output devices, screen, printer, DVD burner, etc..
Advanced Computer
The techniques used to manufacture these machines have changed enormously since the 1940s and have become a technology (that is to say, organized around an industrial techniques) full since the 1970s. Many still use the concepts defined by John von Neumann, although this architecture is in decline: the programs do not change over themselves (which would be considered bad programming practice), and the material takes into account this new gives between now significantly storing instructions and data, including the caches.
The architecture of von Neumann's computer broke down into four distinct parts:
the arithmetic logic unit (ALU) or processing unit: its role is to perform basic operations, one much like a calculator;
control unit. This is equivalent to fingers actuating the calculator;
memory that contains both data and program that will tell the control unit to the calculations on that data. The memory is divided into RAM (programs and data during operation) and memory (programs and data base of the machine);
Input-Output: devices that can communicate with the outside world.
UAL and UA
The arithmetic logic unit or ALU is the element that performs the basic operations (addition, subtraction ...), logical operators (AND, OR, NOR, etc..) And comparison operations (for example the comparison of tie between two areas of memory). Is that the ALU performs the calculations of the computer.
The control unit takes its instructions in memory. They tell him what she should order the UAL
and how it may have to act according to the results that it will provide. Once finished, the control unit is going to the following statement or to another statement in which he directs the program to connect.
The control unit facilitates communication between the arithmetic and logic unit, memory and peripherals. It supports most of the execution of instructions in the computer.
Memory
Within the system, the memory can be described as a series of numbered cells, each containing a small amount of information. This information can be used to tell the computer what to do (instructions) or contain data to be processed. In most architectures, it is the same memory that is used for both functions. In massively parallel computers, it even admits that the program instructions are substituted for others during the operation when it results in greater efficiency. This practice was once common, but the requirements of readability of software engineering have been declining, except in this particular case, for several decades.
This memory can be rewritten as many times as necessary. The size of each block of memory and the technology used varied depending on the costs and requirements: 8 bits for telecommunications, 12-bit for instrumentation (DCS) and 60 bits for big scientific computers (Control Data). A consensus was eventually found around byte addressable as a unit and instructions on size 4 or 8 bytes.
In all cases, the byte is addressable, which simplifies writing programs.
The techniques used to make submissions have included electromechanical relays, mercury tubes in which acoustic waves were generated, individual transistors, ferrite toroids and finally integrated circuits include millions of transistors.
Input-Output
The device input / output enables the computer to communicate with the outside. These devices are very important, the keyboard on the screen.
The common point between all input devices is that they convert the information they retrieve from the external data understandable by the computer. Conversely, output devices decode the information provided by the computer to make it understandable by the user.
Computer Bus
These parts are connected by three buses, the address bus, data bus and control bus. A bus is a grouping of a number of electrical conducting a son to carry on the binary information encoded on several bits.
The address bus carries the addresses generated by the CPU (Central Processing Unit) to select a memory cell or an internal register of one of the blocks. The number of bits conveyed by this bus depends on the amount of memory that must be addressed.
The data bus carries data between the various elements of the system.
The control bus carries the different timing signals needed for operating the system: read signal (RD), write signal (WR), select signal (CS: Chip Select).
Architecture
Miniaturization can integrate UAL and control unit within a single integrated circuit known as the microprocessor.
Typically, the memory is located on integrated circuits near the CPU, a part of this memory, the cache can be located on the same integrated circuit as the UAL.
The whole is, on most architectures, complete with a clock speed processor. Of course, we want it to be as fast as possible, but we can not increase his speed without limits for two reasons:
More clock is faster and the processor generates heat (as the square of the frequency). Excessive temperatures may damage the processor; there is a pace where the CPU becomes unstable and it generates errors that most often lead to a crash.
The trend was from 2004 to consolidate several LGUs in the same processor or multiple processors in the same chip. Indeed, the progressive miniaturization (see Moore's Law) permits with little change in cost. Another trend, since 2006, ARM, is to microprocessors without clock: half of the heat dissipation effect is due to clock signals when the microprocessor works, again, without a microprocessor clock is consuming almost zero when it not work: the only clock signal is then necessary for the refreshment of memories. This advantage is important for portable models.
The main functional difference today compared to the model of Von Neumann is the presence on some architectures of two different caches, one for instructions and one for data (whereas the von Neumann model specified a common memory for both) . The reason for this discrepancy is that the modification by a program's instructions is now considered (except for highly parallel machines) as a practice to be avoided. Therefore, if the cache data must be rewritten in main memory when it is amended, known as the instruction cache will never be, hence simplifying circuits and performance gains.
Instructions
The instructions that the computer can understand are not those of human language. The hardware knows just run a limited number of instructions defined. Typical instructions understood by computers are "copy the contents of cell 123 and placed in cell 456", "add the contents of the cell 321 to cell 654 and place the result in cell 777" and " if the contents of the cell 999 is 0, execute the instruction in cell 345 ". But most of the instructions consist of two zones: one showing what to do, called the opcode, and the other indicating where do we call operand.
Within the computer, the instructions correspond to codes - the code for a copy being for example 001. The set of instructions that a computer supports is called its machine language, language that is a sequence of binary digits, because the instructions and data that is understood by the processor (CPU) consists only of 0 (zero) and 1 (one). 0 = electric current does not pass. 1 = electric current passes.
In general, programmers no longer use such language, but go through what we call a high-level language which is then converted into binary language with a special program (compiler or interpreter as needed). The resulting programs are compiled programs understandable by the computer in his native language.
Some programming languages such as assembler are called low-level languages for the instructions they use are very similar to those of the computer. Programs written in these languages are thus very dependent on the platform for which they were developed. The C language, much easier to read than assembler, thus allows programmers to be more productive. For this reason, we have seen more and more used as material costs fell and hourly wages of programmers increased.
Software
Computer software is a long list of instructions executable by a computer. Many programs contain millions of instructions, made some repeatedly. Nowadays, a personal computer running billions of instructions per second.
Since the mid-1960s, computers running multiple programs simultaneously. This is called multitasking. This applies to all computers today.
In fact, each processor performs a heart program at a time, from one program to another whenever necessary. If the speed of the processor is sufficiently large compared to the number of tasks to perform, the user will feel a simultaneous execution of programs. Priorities for the various programs are generally managed by the operating system.
Operating System
The operating system is the central program that contains the basic programs needed for the proper functioning of computer applications. The operating system allocates physical resources of the computer (CPU, memory ...) with various programs running. It also provides tools to software (such as pilots) to facilitate the use of different devices without having to know the physical details.
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