The Pre-Computer Age
- The Abacus -- earliest computing tool, uses strings of beads to perform computations.
- Oughtred's Slide Rule
- Introduced in 1621 and continued in popular use until the 1970s
- Used specially marked rulers to perform computations
- Pascal's Calculator
- A mechanical calculator invented in 1642
- Rotating gears performed addition and subtraction
- Leibnitz's Multiplier
- Introduced in 1673
- Improvement on Pascal's calculator and could multiply and divide directly.
Programming and Expanding the Machine -- Industrial Revolution
- Jacquard's Loom
- Used punched cards to store the pattern woven in cloth
- Punched cards used as a storage medium was incorporated into the design of calculating devices.
- Charles Babbage
- Difference Engine -- device designed to accurately and automatically calculate mathematical tables.
- Analytõcal Engine -- designed in 1833 was a complete computer containing punched card input, an output device, a processor, and memorv. A working version was not completed in Babbage's lifetime.
- Hollerith's Census Machine
- Tabulating device that assisted the US Census Bureau in calculating the 1890 and 1900 census
- Used punched cards to store information
- Company Hollerith founded was the cornerstone of what eventually became IBM Corporation.
- Burroughs' Adding/Listing Machine -- 1888 invention to do basic arithmetic and list the results, found widespread application especially in business.
The Computer Age -- from calculating devices to computers
- Atanasoff's ABC
- Prototype computer that used vacuum tubes for internal components and punched cards for output.
- Atanasoff designed a memory drum and arithmetic unit.
- ABC stands for Atanasoff Berry Computer
- Germany's Wartime Computer -- designed a prototype computer that used electromagnetic relays as internal components.
- England's Wartime Computer
- In 1943 British built COLOSSUS the first special-purpose electronic computer.
- Used exclusively to break German codes.
- Developed with the help of Alan Turing
- Room-sized machine consisting of 1800 vacuum tubes with paper tape as input.
- American Wartime Computer Research
- Harvard Mark I
- ENIAC
- General purpose computing device (1943) designed by Howard H. Aiken, a Harvard professor, in association with IBM and the US Navy.
- Used electromagnetic relays as internal components and paper tape for input.
- Had no memory component.
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- General purpose computer (1946) designed by John Mauchly and Presper Eckert, professors at the Univ. of Penn., in association with the US government.
- Used over 18,000 vacuum tubes as internal components and contained circuitry for storing information (memory)
- Von Neumann's Logical Computer -- von Neumann devised a means of storing program instructions in memory using numeric (binary) codes. His theoretical machine consisted of single function components, which still form the basis for today's machines.
- EDSAC -- first computer to incorporate the stored program concept.
- EDVAC -- first machine designed to incorporate von Neumann's architectural design and to use his binary code for storing instructions.
- UNIVAC I -- first computer designed and marketed for business.
- IBM 650 -- first IBM computer, marketed to business community.
- Grace Murray Hopper developed the first translator program in 1952. In 1959 she led the way in the development of COBOL the first business language.
A Computer Genealogy
- First-Generation Computers (1951-1958)
- Used vacuum-tube technology.
- Programmed in machine language.
- Second-Generation Computers (1959-1964)
- Used transistors
- Made computers smaller and more reliable.
- While assembly language was popular, both FORTRAN and COBOL were created during the second generation.
- Third-Generation Computers (1965-early 1970s)
- Miniaturization packed hundreds of transistors on a tiny silicon chip
- Wide variety of VO devices were invented
- English-like programming languages and prewritten packages became popular.
- Fourth-Generation Computers (early 1970s-present)
- Micro-miniaturization of internal components
- Development of the microprocessor
- Prewritten software popular
- Machine sizes to fit wide range of user needs
The Rise of the Microcomputer
- Computers from a Kit
- Altair 8800 invented in 1975 by Ed Roberts for hobbyists, required assembly by user
- Apple I invented in 1976 by Stephen Jobs and Stephen Wozniak. Designed for non-hobbyist, it was easy-to-use, easy-to-assemble and inexpensive.
- The Birth of the Personal Computer
- Apple II released in 1979 as the first assembled microcomputer. VisiCalc, the first electronic spreadsheet, was packaged and sold along with the Apple II.
- Personal Computer (PC) was released by IBM in 1981. IBM encouraged other hardware and software manufacturers to develop products that could be used with the PC.
- Towards a User-Friendly Machine
- In 1984, Apple released the Macintosh which featured a pointing device called a mouse and icons representing common computer tasks. Macintosh was designed to be easy to use.
- The IBM PS/2 and Apple Macintosh II are released in 1987. By 1991, with the development by Intel of a new class of powerful but inexpensive microprocessor chips (80286, 80386, 80486) IBM had lost its dominance in the microcomputer market.
- In 1988 the NeXT machine is released. It is a powerful workstation designed to appeal to the microcomputer user. It combines state-of-the art processor chips with high-fidelity sound, graphics hardware, and a revolutionary optical storage
- In late 1990 the Macintosh Classic is released in an effort to compete with low cost Intel-based machines.
Beyond the Fourth Generation -- will be based on new developments in computer technology developed in US and Japan. Likely to include: super-chips, parallel processing, artificial intelligence, natural language.