Personal Computer

In this generation the auxiliary memories were extended and they were created magnetic disks of great capacity. The printers were designed and optical readers and were developed the programming languages, appear the new programming languages denominated High-level languages. Third generation 1965-1975 is characterized by the appearance of the integrated circuits realised with silicon, the increase of the speed, the greater number of programs and languages: Cobol, Fortran and the appearance of the terminals to transmit data to the central processor at a distance, or vice versa. They appear the operating systems for the control of the computer, central depots of data to which it is possible to be acceded simultaneously from several users. The first apparatus based totally on integrated circuits is IBM series 360 that incorporated in addition an Operating system for the control to the machine.

In the middle of the 70 they appear the first minicomputers. Fourth generation the 1975-1990 most important characteristic of this generation is the appearance of the microprocessors Chip, that are circuits with great amount of transistors integrated in a small space. Other characteristics are the increase of the entrance capacity and exit of data, major duration of the components, new programming languages Logo, Pascal, BASIC, data bases. Intelligent terminals with own memory arise and the word processors. It is reduced of the size and cost of the computers and improves the speed of calculation. A new era with the appearance of the Personal computers or Personal Computer is abre.

The first microcomputers had a price both superior to million pesetas. At the end of the 80, the price was on the two hundred thousand pesetas and its yield was 100 times greater. At this time it emphasizes the development of the operating systems, that look for an integration between the user and the computer, through the use of graphs. Fifth generation 1990-hoy the revolution arrives with the microprocessors of new generation. The speed goes off and the successive generations of microprocessors follow one another, becomes general the personal computer. The alliances between rival companies are tonic of this time, IBM signs agreements with Apple and Motorola, for the production of a new series of denominated microprocessors PowerPC. Intel sends the Pentium microprocessor like answer to this alliance. In agreement they advance the years the speed and the yield of the microprocessors is greater thanks to the advances in microelectronics. It is necessary to emphasize that on the other hand other companies continue working in supercomputers that incorporate several microprocessors in the same machine. According to Law of Moore the number of transistors by microprocessor duplicate every 18 months. One has turned 30 years in the last and it is anticipated is fulfilled during next the 20 years.