Since 1975 in the USA the mass production of the personal computers (PC) was begun. This event often call the second information revolution (the first information revolution is considered emergence of the press and publishing – 1445). The personal computer appeared on the basis of the mini-and micro COMPUTER for ensuring personal calculations, i.e. for work of the expert in this or that subject domain on the workplace. The user could sit down at the personal computer display – the nonprofessional in programming. Since 1981 the personal COMPUTERS having a block and modular design began to be issued. These easy-to-work and rather cheap cars intended for the consumers who aren't possessing knowledge in the field of computer facilities and programming. The wide circulation of the mini computer in the early seventies was defined by need to approach the computer to the user. Mini computers were installed at the enterprises and in the organizations where use of big COMPUTERS was economically unprofitable.
Thus, the personal computer is the computer intended for individual use. Now it is the powerful universal computer; it successfully works as at home, and at workplaces at offices, is easily connected to various computer networks.
The main criteria of reference of the computer to class personal computer – the small sizes, lack of need for service, the low price, functional universality and simplicity of modernization.
As the microprocessor forms a technical basis of the personal computer, their development defined alternation of generations of personal COMPUTERS:
- 8-digit microprocessor (1975 - 1980);
- 16-digit (1981 - 1985);
- 32-bit (1986 - 1992);
- 64-digit (1993 – to the present).
The important role in development of the personal computer was played by emergence of the IBM PC computer made by IBM corporation (USA) on the basis of the Intel-8086 microprocessor in 1981. This personal computer took a leading place in the market similar. Its main advantage – so-called open architecture thanks to which users can expand possibilities of the acquired COMPUTER, adding various peripherals and upgrading the computer. Further other firms started creating the personal computers, but the IBM PC computer became a certain standard in a class of personal computers. Today more than 85% of all sold PEVM are based on architecture of IBM PC.
To destination personal computers classify on household, general purpose and professional.
Household and general purpose of PEVM are intended for the mass consumer therefore they have to be rather cheap, reliable and have, as a rule, a simple basic configuration. Personal computers use in house conditions for entertainments (video game), training, etc. At the same time the architecture of these cars allows to connect them to communication channels, to expand a set of the peripheral equipment. Such computers also are used for work with the text, solutions of scientific and engineering tasks. Users nonprofessionals work at the personal computer of general purpose, first of all. Therefore such computers are supplied with the developed software including operating systems, translators from algorithmic languages, packages of applied programs.
Professional PEVM are applied in the scientific sphere to the solution of complex information and production challenges where are required high speed, effective transfer of big arrays of information, rather big capacity of random access memory.
Thanks to connection of a big set of peripherals, functionality of the personal computer considerably extends. They can work in a multitask mode, with algorithmic languages of high level, as a part of computer networks. On the functionality the multiprocessor professional PEVM not only come nearer to big COMPUTERS of the previous generation, but also can quite compete with them.