History of Computers Week 2

Introduction

• The term "computer" initially referred to humans performing calculations, recorded as early as 1613.
• Human computers required extensive training in mathematics for specialized tasks.

Evolution of Computers

• Six generations of computers exist: pre-modern era, first, second, third, fourth, and fifth generations.
• Pre-modern era includes manual-mechanical, electromechanical, and electronic devices.

Pre-modern Era Devices

• Manual-Mechanical Devices: Operated manually by users.

  • Tally Sticks: Ancient memory aids for documenting numbers.
  • Abacus: Considered the first computing device, using beads to perform calculations; invented in China.
  • Napier’s Bones: Created by John Napier in 1614 for arithmetic calculations.
  • Oughtred’s Slide Rule: Mechanical device for multiplication and division, invented by William Oughtred.
  • Pascaline Calculator: Mechanical adding machine by Blaise Pascal, introduced in 1642.
  • Stepped Reckoner: Invented by Gottfried Wilhelm Leibniz in 1672; performed basic arithmetic operations.

• Babbage’s Engines:

  • Difference Engine: Automated computation of mathematical tables by Charles Babbage.
  • Analytical Engine: A fully automatic machine capable of any calculation.

• Arithmometer: Invented by Thomas de Colmar in 1820; became the first commercially successful calculator.

Electronic Devices

• Developed using circuit boards and transistors, moving away from mechanical relays.
  • ABC (Atanasoff-Berry Computer): The first digital computer for solving simultaneous equations.
  • ENIAC (Electronic Numerical Integrator and Calculator): The first fully electronic general-purpose digital computer.

Generations of Computers

• First Generation (1951-1958): Utilized vacuum tubes; processing speed of 1,000 instructions/sec.

  • Notable examples: UNIVAC (first commercial computer) and IBM 701.

• Second Generation (1959-1963): Featured transistors; processing speed of 1,000,000 instructions/sec.

  • Example: TRADIC, the first transistorized computer.

• Third Generation (1964-1970): Introduced integrated circuits; processing speed of 10,000,000 instructions/sec.

  • Example: IBM System/360, used widely in business and science.

• Fourth Generation (1971-present): Microprocessors or large-scale integrated circuits; processing speed over 100,000,000 instructions/sec.

  • Introduction of GUIs and the networked environment leading to the Internet.

• Fifth Generation (Present-Future): Focuses on Artificial Intelligence (AI); uses parallel processing and superconductors for advanced capabilities.

Classification of Computers

• According to Purpose:

  • General-Purpose Computers: Versatile machines like PCs, capable of running various applications.
  • Digital Computers: Specialized for counting; operates on discrete values.
  • Analog Computers: Handle continuous variables; used in scientific and engineering applications, e.g., speedometers.
  • Hybrid Computers: Combine features of analog and digital computers for specialized tasks.

• According to Capacity:

  • Supercomputers: The most powerful in speed and accuracy; execute trillions of instructions per second (FLOPS).
  • Mainframe Computers: Large systems for multiple simultaneous user access; handle massive data volumes.
  • Minicomputers: Mid-range devices popular in late 1960s; now largely replaced by personal computers.
  • Microcomputers: Small, affordable, and widely used; commonly known as personal computers (PCs).

This quiz covers the fundamental concepts of the history and evolution of computers. It explores different generations and classifications of computers based on purpose, data handling, and capacity. Test your knowledge on the milestones in computer development and their classifications.