As we know that the computer system is developed in different years. So, the development of computer systems in different generations is known as Computer Generation.
1st Generation of Computer (1946-59)
The computer of this generation was entirely electronic. Vacuum Tubes are used to store instructions. And Magnetic Drums for Memory. First Generation computer system was very slow for Input and Output. This computer system understood only low-level programming languages. So, It is very expensive to operate.
Examples of 1st generation computer systems are ENIAC, IBM-650, UNIVAC, and more.
2nd Generation of Computer (1959-65)
In this generation of computer vacuum tubes replaced by Transistors. In this computer generation, the size of the computer systems is decreased. The speed of Input and Output is was increased. In this generation of computer Assembly Language and Puch Cards used for Input. Constant maintenance was required. And the computers were used for specifics purposes.
Examples of 2nd generation computer systems are CDC 1604, IBM-1401, Honeywell-200, and more.
3rd Generation of Computer (1965-71)
In this generation, the computer systems were based on Integrated Circuit (IC Chips). IC Chips were invented by Robert Noyce and Jack Kilby. These computer systems are the cheapest as compared to second-generation computers. The speed and storage capacity of computers were increased and the size of the computer system of the third generation was decreased. In this generation, computer systems use a mouse and keyboard as input devices. The Operating System comes in this generation.
Examples of 3rd generation computer systems are PDP-8, PDP-11, IBM-360, and more.
4th Generation of Computer (1971-80)
The time period of the fourth generation is from 1971 to 1980. Microprocessors were used in these computer systems. The microprocessor was used to perform Arithmetic and Logical Functions. In these computer systems, Large Scale Integrated circuits were used. The storage capacity and speed were increased and the heating problem decreased. High-Level Programming Languages used in these computer systems.
Examples of 4th generation computer systems are IBM-4341, IBM PC-XT, and more.