Computer generation is the classification of computers into different groups according to their manufacturing date, other hardware and software technology used inside those computers. Based on various stages of development, computers can be divided into five different generations.
First Generation Computer
The period of first-generation computers was 1940-1956. These computers used vacuum tubes as the main technology, making them large, slow, and consumed enormous amounts of energy, but they laid the foundation for modern computing.
Key Features:
Technology Used: Vacuum Tubes
Operating Speed: Millisecond range (10^-3 sec).
Operating System: No operating system; manual programming.
Programming Language Used: Machine Language and assembly language
Input/Output: Punched cards and paper tape for input; printers for output.
Memory Used: - Primary Memory: Magnetic Core Memory
- Secondary Memory: Magnetic drum, Magnetic tape
Second Generation Computer
The period of second generation computer was 1959 -1965. In this generation, vacuum tubes were replaced with transistors, making computers smaller, faster, more reliable, and energy-efficient.
Key Features:
Technology used: Transistors
Operating Speed: Macro second range(10-6 sec)
Programming Language Used: Assembly language and high-level programming languages like FORTRAN, COBOL were used.
Operating System: Batch processing and multiprogramming Operating system
Input/Output: Punched cards for input,printers and tape drivers for output.
Memory Used:
- Primary Memory: Magnetic Core (first computers that stored their instruction in their memory)
- Secondary Memory: Magnetic Tap and Magnetic disks
Examples: IBM 1401, IBM 7090, CDC 1604
Third Generation Computer
The period of third-generation computers was 1965-1971. In this generation, integrated circuits (ICs) replaced transistors packing multiple transistors onto a single chip. This breakthrough made computers even smaller, faster, and more powerful, paving the way for widespread commercial use.
Key Features:
Technology Used: Integrated circuits (ICs).
Operating Speed: Nanosecond range (10^-9 sec).
Programming Language Used: High-level languages like FORTAN, COBOL, BASIC, Pascal, and C,C++ etc.
Operating System: Time-sharing, remote processing and multiprogramming operating systems.
Input/Output: Keyboards and monitors for input/output
Memory Used:
Primary memory: Semiconductor memory
Secondary memory: Magnetic tape, Magnetic disk like floppy disk, hard disk etc
Examples: IBM 360 series, PDP-8, UNIVAC 1108.
Fourth Generation Computer
The period of fourth-generation computers was 1971-1980. In this generation, microprocessors were introduced, which combined all computer components onto a single chip. This innovation made computers affordable, compact, faster, and more reliable. Intel was the first company to develop a microprocessor.
Key Features:
Technology Used: Microprocessors (built using VLSI technology).
Operating Speed: Picosecond range (10^-12 sec).
Programming Language Used: High-level languages like C, C++, and Java.
Operating System: Graphical user interface (GUI) operating systems.
Input/Output:Advance I/O devices like Keyboards, mouse, scanner,touch screen, monitors, and printers.
Memory Used:
- Primary: Semi-conductor memory
- Secondary Memory: Magnetic tape, Magnetic Disk, Optical Memory(CD/DVD/Blue ray), Flash Memory (Pen drive, memory card)
Examples: Mac book, IBM PC, HP laptop.
Fifth Generation Computer
The period of fifth-generation computers began in 1980 and continues today. This generation focuses on artificial intelligence (AI) and parallel processing.
Key Features:
Technology Used: ULSI (Ultra Large Scale Integration)
Operating Speed: Femto second range
Programming Language: Natural language
Input/Output: touchscreens, voice recognition, and gesture control.
Examples: IBM Watson, Google Quantum Computer, AI-powered devices.