The current generations of computers combine hardware and software to create a complete computer system. However, in the past, the term “generation“ in computing language referred to advancements in a computer’s hardware. It was initially used to differentiate between various hardware technologies.

Mathematicians and inventors employed mechanical calculators to lessen the computational strain because there were no current computing applications or tools like graphing calculators, spreadsheets, or computer algebra systems.

• Eight mechanical calculators existed before the modern computer was created.

1. Abacus (ca. 2700 BC)
2. Pascal’s Calculator (1652)
3. Stepped Reckoner (1694)
4. Arithmometer (1820)
5. Comptometer (1887) and Comptograph (1889)
6. The Difference Engine (1822)
7. Analytical Engine (1834)
8. The Millionaire (1893)

Early computers were less sophisticated than they are now, but they underwent several adjustments before becoming what they are today.

It keeps getting faster, more accurate, significant, and affordable. It is convenient to divide this extensive period into later stages known as computer generations:

• First Generation Computers (1940-1956)
• Second Generation Computers (1956-1963)
• Third Generation Computers (1964-1971)
• Fourth Generation Computers (1971-Present)
• Fifth Generation Computers (Present and Beyond)

First Generation of Computers (1940-1956)

Vacume tubes were used in first-generations computers. They came into being between 1940 and 1956. The examples of the first computer generations are:

First-generation computer examples include:

• ENIAC
• EDVAC
• UNIVAC
• IBM-701
• IBM-750
• UNIVAC-1 (Universal Automatic Computer)

 2nd Generation of Computer (1956-1963)

This generation’s computers used transistors. It supported high-level programming languages like FORTRAN and COBOL, as well as assembly language.

The examples of second-generation computers:

• IBM 1400 series
• IBM 1620
• IBM 7094 series
• CDC 1604
• CDC 3600
• UNIVAC 1107

3rd Generation of Computer (1964-1971)

Integrated Circuits are the foundation for third-generation computers (ICs). It supported operating systems allowing remote time-sharing, processing, and multi-programming. Memory in this generation of computers is magnetic tape/disk with a large magnetic core.

A list of high-level languages currently in use:

• FORTRAN-II
• COBOL
• PASCAL PL/1
• BASIC
• ALGOL-68

Examples of third generation are:

• UNIVAC 1108
• UNIVAC AC 9000
• IBM-370/168
• IBM-360 series
• Honeywell-6000 series
• PDP (Personal Data Processor)
• TDC-316

4th Generations of Computers (1971-1980)

The fourth generation of computers was built on Very Large, Scale Integrated (VLSI) circuits and employed distributed operating systems, real-time networks, and time-sharing.

This generation used all high-level programming languages, including C, C++, DBASE, etc. From 1971 until 1980, the fourth generation of computers was produced.

4^th generation computer are uses semiconductor memory, including RAM (Random Access Memory) and ROM (Read Only Memory).

4th generation computer examples:

• Apple Macintosh
• IBM PC
• DEC 10
• STAR 1000
• PDP 11
• CRAY-1 (Super Computer)
• CRAY-X-MP (Super Computer)

5th Generation of Computer (1980 to till date)

The Ultra Large-Scale Integration (ULSI) platform is the foundation for fifth-generation computers, which offer AI (Artificial Intelligence) software and hardware parallel processing. This generation uses all high-level languages, including Java, .Net, C, and C++. It can comprehend natural language or human language since it supports AI technology.

An illustration of a fifth-generation computer:

• Desktop
• Laptop
• Notebook
• Ultrabook
• Chromebook

A comparison among Generations of Computers