The first generation (1945-1954) - computers on electronic lamps, such, as in old TVs. The majority of machines of the first generation were experimental devices and were under construction for the purpose of check of those or other theoretical positions. Weights and the sizes of these computer dinosaurs which quite often demanded for itself separate buildings, became for a long time a legend. As founders of a computer science by right are considered Claude Shennon - the founder of the theory of the information, Alan Tjuring - the mathematician who have developed the theory of programs and algorithms, and John a background Neumann - the author of a design of computers which underlies till now the majority of computers. In the same years there was one more new science connected with computer science, - cybernetics. The cybernetics founder is the American mathematician Norbert Wiener.

In the second generation of computers (1955-1964) instead of electronic lamps transistors were used, and as memory devices magnetic cores and magnetic drums - far ancestors of modern hard disks began to be applied. All it has allowed to reduce sharply dimensions and cost of computers which then began to be under construction for the first time on sale. But the main achievements of this epoch belong to area of programs. On the second generation of computers for the first time there was that is called today as an operating system. Then the first languages of high level - the Fortran, Algol, have been developed by Kobol. These two important improvements have allowed to simplify and accelerate a writing of programs for computers considerably. Also, the sphere of application of computers extended also. Already not only scientists could count on access to computer facilities; computers have found application in planning and management, and some large firms even computerised the accounts department. Computers of the third generation.