The electronic era includes the period from 1940 to the present. Electronic vacuum tubes replaced electromechanical relays – switches. In 1939, a prototype with 300 tubes was built in the United States.
During World War II, Alain Turing was engaged in solving the problem of decommissioning German secret messages. His approach to this problem was based on finding a machine that would be able to solve every problem posed by a series of elementary operations, and the memory should have been large enough to store the instructions required for the account. He gave an abstract model of such a machine known as the „Turing Machine“. It contained 1800 pipes and could count quickly.
These machines made incredible noise during work.
During the Second World War, Americans developed for the first time a fully electronic computer ENIAC (Electronic Numerical Integrator and Computer), the first real computer. It was made in November 1945. He worked on the principle of electronic pipes and was primarily intended for the needs of the army. It occupied a space of 139 square meters, it had 19,000 thermionic tubes and diode and weighed about 30 tons.
The computer was warming up very quickly and there was a problem with the pipes. The heat also attracted insects that were drawn in the pipes and caused errors in the operation and transmission of data.
Because of this, computer errors are still called bug (bag, insect). ENIAC could not remember the program in memory, it was already incorporated into electronic circuits.
The basic principles of the architecture of today’s computers were given by John von Neumann. He made a difference between the physical part of the computer – the hardware and logical part of the computer – the software.
He started working in 1943 at the Los Alamos Laboratory on the EDVAK project together with John Mockley and John Ekert. They invented the first fully electronic computer that worked on the basis of a predetermined program.