It was invented by a computer. The word «computer» means «computer», ie a device for computing. The need to automate the processing of data, including computing, there is a very long time. Many thousands of years ago to an account used by counting sticks, stones, etc. More than 1500 years ago (and perhaps much earlier) to facilitate the calculations have used the abacus.
In 1642 Blaise Pascal invented a device that mechanically performs the collapse of numbers, but in 1673 Gottfried Wilhelm Leibniz adding machine designed to mechanically perform four arithmetic operations. Since the XIX century. comptometer received a very broad application. They performed very complex calculations, such calculations of ballistic tables for artillery firing. There was, and a special profession - the counter - a man who works with the adding machine, quickly and accurately observe a sequence of instructions (a sequence of instructions later became known as the program). But many calculations are very slow - even tens of counters must have been working for several weeks and months. The reason is simple - if such calculations performed by the choice of action and record the results produced by man, and the speed of his work is very limited.
In the first half of the XIX century. English mathematician Charles Bebbidzh tried to build a universal computing device - Analytical car, which was to perform computations without human intervention. To that end, she was able to execute the program, introduced with the help of punched cards (cards of thick paper with information applied through the holes, they are already widely used in weaving machines), and a «warehouse» for storing data and interim results ( in modern terminology - memory). Bebbidzh was unable to complete work on the development of an analytic machine - it proved too difficult for the technology of the time. However, he has developed all the basic ideas, and in 1943 the American Howard Achen with the help of Bebbidzha based technology in the XX. - Electromechanical relays - was able to build a business from IBM a machine called «Mark-1». Bsche earlier ideas Bebbidzha were pereotkryty German engineer Konrad Tsuze, who in 1941 built a similar car.
By this time the need for automating calculations (including for military purposes - ballistics, cryptography, etc.) has become so great that to create the type of machines built by Eike and Tsuze simultaneously worked several groups of researchers. Since 1943, a group of specialists under the leadership of John Mochli and Prespera Eckert in the U.S. beginning to construct such a machine is already on the basis of electron tubes, rather than relays. Their machine, called ENIAC, has worked a thousand times faster than the Mark-1, however, to specify its programs accounted for several hours or even days necessary to connect to wires. To simplify the process of job programs, Mochli and Eckert began to construct a new machine that could keep the program in his memory. In 1945, was brought to the famous mathematician John von Neumann, who prepared a report on this machine. The report was distributed to many scientists and was widely known because it Von Neumann clearly and simply articulated the general principles of operation of computer devices, ie computers.
The first computer, which embodies the principles of von Neumann, was built in 1949, the British researcher Maurice Wilkes. Since then, computers have become much more powerful, but the vast majority of them done in accordance with the principles set out in its report in 1945 by John von Neumann. Explain why these principles.
As there were personal computers. Computers 40's and 50-ies were very large devices - large halls were making cabinets with electronic equipment. All this has cost very dearly, and computers were available only to large companies and institutions. But in the fight for buyer firms producing computers and electronic equipment for them, sought to make their products faster, leaner and less expensive. Thanks to modern technology in this direction have been achieved truly remarkable results.
The first step to reducing the size of computers has been made possible with the invention in 1948 of transistors - tiny electronic devices that are able to replace computers in electronic tubes. In the mid 50-ies have found a very cheap means of production of transistors, and in the second half of 50-ies have computers based on transistors. They were hundreds of times smaller tube computers of the same productivity. The only part of the computer, where transistors were unable to replace electronic tubes - is memory, but instead of bulbs were used invented by the time the scheme of memory for magyit by the cores. By the mid 60-ies appeared much more compact external devices for computers, which enabled the company Digital Equipment published in 1965, the first mini-computer PDP-8 size of a refrigerator and cost 20 thousand dollars. But by that time had been prepared yet another step towards miniaturization of computers - integrated circuits were invented.
Before the advent of integrated circuits transistors manufactured separately, and when they had to build circuits and solder to connect manually. In 1958, Jack Kilby invented, as one plate to get a few semiconductor transistors. In 1959, Robert Neuss (future founder of Intel) has invented a better method to create on one plate and transistors, and all the necessary connections between them. These electronic circuits have become known as integrated circuits, or chips. In (hereinafter the number of transistors that have been able to locate per unit area of integrated circuits, increased approximately doubled every year. In 1968 the company Burroughs has released the first computer integrated circuits, and in 1970 the firm Intel start selling integrated circuits memory.
In the same year was taken another important step on the path to a personal computer - Marshian Edward Hoff from the same company Intel designed integrated circuit, similar in function the central processor mainframe. For the first microprocessor Intel-4004, which was released for sale at the end of 1970, of course, the possibility of Intel-4004 were much more modest than the CPU mainframe - he worked much more slowly and could handle while only 4 bits of information (CPU mainframe handled 16 or 32 bits at a time). But in 1973 the company released an Intel 8-bit microprocessor Intel-8008, and in 1974 - an enhanced version of its Intel-8080, which until the late 70-ies became the standard for the microcomputer industry.
Initially, these chips are used only electronics-lovers and various specialized devices. But in 1974, several companies announced the creation of a microprocessor based on Intel-8008 computer, that is the device performs the same function as the mainframe. In early 1975, the first commercially distributed computer Altair-8800, built on Intel-based microprocessor 8080. This computer, developed by MGG8, sold at a price of around 500 dollars. While his ability was very limited (RAM was only 256 bytes, keyboard and the screen missing), his appearance was greeted with great enthusiasm. In the first month was sold several thousand sets of machines. Buyers of the computer supplied him with additional devices: a monitor to display information, keyboard, extended memory, etc. Soon, these products are produced by other firms. In late 1975, Paul Allen and Bill Gates (future founder of Microsoft) created for the computer «Altair» interpreter language Basic, which allowed users to easily communicate with a computer and easily write programs for it. This also contributed to the popularity of computers.
The success of the company MITS forced many firms to engage in the production of personal computers. There, and several magazines on personal computers. Computers have been sold already in full bundling, keyboard and monitor the demand for them was dozens and then hundreds of thousands of units per year. The increase in sales is contributed many useful programs designed for business applications. There and in a commercially available program such as a program for editing text WordStar and Games VisiCalc (respectively 1978 and 1979.). These (and many others) programs made for business purchases of computers very profitable investment of money: they may become much more efficient to carry out accounting, drafting, etc. As a result, it turned out that for many organizations, they need to perform calculations has been made possible not to mainframe or mini-computers and on personal computers, which is much cheaper.