Apple Computer Design Evolution

 evolution of computers started way back in the late 1930s. Binary arithmetic is at the core of the computers of all times. History of computers dates back to the invention of a mechanical adding machine in 1642. Abacus, an early computing tool, invention of logarithm by John Napier and the invention of slide rules by William Oughtred were significant events in the evolution of computers.
Evolution of computer technology can be divided into five generations.
First generation computer consisted of vacuum tubes and they were used from 1943-1958. ENIAC (Electronic Numerical Integrator and Calculator) computer is an example of first generation computer.
Second generation (1959-1965) computer consisted of transistors i.e. vacuum tubes were replaced by transistors. Thus the size of the computer got reduced considerably.
Third generation (1966-1973) computer consisted of integrated circuits (IC) i.e. many transistors in single silicon chip. A single IC has many transistors, registers and capacitors built on a single thin slice of silicon.
With the invention of microprocessor (1971), fourth generation of computer evolution started and present day computers are also categorized in the fourth generation.
The fifth generation computers are under development. They are going to be based on principles of artificial intelligence and natural language recognition. Developers are aiming at computers capable of organizing themselves.