I.
Early Computing Devices (Before 1800s)
1. Abacus (c. 3000 BCE) – A simple counting tool using beads on rods.
2. Antikythera Mechanism (c. 100 BCE) – An ancient Greek device used to predict
astronomical positions.
3. Pascaline (1642) – A mechanical calculator invented by Blaise Pascal.
4. Jacquard Loom (1801) – A loom that used punched cards to automate weaving
patterns, an early form of programming.
II. Mechanical and Electromechanical
Computers (1800s – 1930s)
1. Difference Engine (1822) – A mechanical calculator designed by Charles Babbage to
compute polynomial functions.
2. Analytical Engine (1837) – A general-purpose mechanical computer designed by
Babbage; included concepts like loops and conditional branching.
3. Hollerith Tabulating Machine (1890) – Used punched cards to process census data;
created by Herman Hollerith.
III. First Generation Computers (1940s –
1950s) – Vacuum Tubes
1. Vacuum Tube – An electronic component that controls electric current flow; used as the
first computing switches.
2. ENIAC (1945) – The first general-purpose, fully electronic digital computer.
3. UNIVAC I (1951) – The first commercially available computer in the U.S.
4. Stored Program Concept – Developed by John von Neumann, allowing programs to be
stored in memory instead of being manually rewired.
IV. Second Generation Computers (1950s
– 1960s) – Transistors
1. Transistor (1947, widely used in 1950s) – A semiconductor device that replaced
vacuum tubes, making computers smaller and more reliable.
2. IBM 1401 (1959) – One of the first widely used business computers.
3. COBOL & FORTRAN (1950s) – Early high-level programming languages developed.
V. Third Generation Computers (1960s –
1970s) – Integrated Circuits (ICs)
1. Integrated Circuit (1958) – A chip containing multiple transistors, developed by Jack
Kilby and Robert Noyce.
2. Minicomputers (1960s – 1970s) – Smaller, cheaper computers used by businesses and
research institutions.
3. The Birth of Software Industry – Companies started creating operating systems and
applications.
VI. Fourth Generation Computers (1970s –
1990s) – Microprocessors & Personal
Computers
1. Microprocessor (1971) – A complete CPU on a single chip; the Intel 4004 was the first.
2. Personal Computers (PCs) (1970s – 1980s) – The rise of computers for individual
users, such as:
○ Altair 8800 (1975) – A DIY computer kit that inspired hobbyists.
○ Apple I & II (1976-1977) – Created by Steve Jobs and Steve Wozniak, one of the
first home computers.
○ IBM PC (1981) – Standardized personal computing with MS-DOS.
3. Graphical User Interface (GUI) (1980s) – Made computers easier to use, popularized
by Apple’s Macintosh (1984) and Microsoft Windows (1985).
VII. Fifth Generation Computers (1990s –
Present) – AI, Internet, and Mobile
Computing
1. Internet & World Wide Web (1990s) – Tim Berners-Lee developed the first web
browser and server.
2. Laptops & Mobile Devices (2000s) – Computing becomes portable.
3. Cloud Computing (2010s) – Services like AWS, Google Cloud, and Microsoft Azure
provide online data storage and computing power.
4. Artificial Intelligence (AI) & Quantum Computing (2020s – Future) – AI-powered
applications and the development of quantum processors push computing into new
frontiers.
