History

• Abacus is the earliest calculating tool
• Blaise Pascal and Gottfried Leibniz - built mechanical calculators using pegged wheels that could perform basic arithmetic functions.
• Charles Babbage (1842) designed an analytical engine that

  performed general calculations automatically.
• Herman Hollerith (1890)

  • designed a tabulating machine to record census data
  • the tabulating machine stored information as holes in scorecards that were interpreted by machines with electrical sensors.
• John Attansoff and Clifford Berry (1939) built the first electronic computer
• In December 1943, the British built the first fully operational computer called Colossus that only encrypts German military codes.
• In 1944, Harvard University developed the first general-purpose modern computer called ASCC (Automatic Sequence Controlled

  Calculator. However, it is exceedingly slow and prone to malfunction
• IN 1946 in University of Pennsylvania, J. Presper Eckert and John Maunchly developed the first general-purpose electronic computer called ENIAC (Electronic Numerical Integrator

  and Calculator). It contained 18000 vacuum tubes and failed

  1 in every 7 minutes
• William Shockley (1948) developed the transistor, an electronic switch that alternately allows or does not allow electronic

  signals. It made the possibility of the development

  of stored program computer
• Eckert and Mauchly (1951) developed UNIVAC (Universal Automatic Computer), the first commercially successful general

  purpose stored electronic digital computer.
• Computer Generations