Computers and Computation

Introduction

To 1790

The abacus of ancient, unknown origin was the first calculating device.   It was used in Egypt by 500 BCE.   It has rows of beads strung on wires.   There are 10 beads on each row, and each row represents a multiple of 10.   The first row represents the units digits, the second row the 10s digits, the third row the 100s digits, and so forth.   An experienced user can add, subtract, multiply and divide on an abacus. ^{Asimov 45}

1790-1799

1800-1809

1810-1819

1820-1829

Between 1821 and 1832, the English mathematician, Charles Babbage, developed a series of Difference Engines (see #1 and #2) to compile mathematical tables.   In 1834, he invented a more general computer called an Analytical Engine, which was as a general symbol manipulator similar to modern computers.   None of his mechanical calculators were commercially successful, but they served to stimulate interest in mechanical and, later, electrical computing machines.

1830-1839

1840-1849

1850-1859

1860-1869

1870-1879

1880-1889

1890-1899

1900-1909

1910-1919

1920-1929

1930-1939

In late 1939, at Iowa State U., Professor John Atanasoff and Clifford Berry, a graduate student, build the first prototype of the modern digital computer.   It uses electricity, vacuum tubes, binary numbers and capacitors.   The prototype wins the team a grant of $850 to build a full-scale model, which they do over the next two years.   It was the size of a desk, weighed 700 pounds, had over 300 vacuum tubes, and contained a mile of wire. ^{Bellis n.p.}

1940-1949

Konrad Zuse, a German engineer, builds the Z3 in 1941, the world's first electronic, fully programmable digital computer based on a binary floating-point number and switching system. ^{Bellis n.p.}

In 1944, Professor Howard Aiken of Harvard U., working with the IBM Co., invents the Automatic Sequence Controlled Calculator (ASCC or Mark 1), which was a huge electromechanical calculator with 3000 relays controlled by punched paper tape.   It took 0.3 seconds to add and subtract, 4.0 seconds to multiply and 12.0 seconds to divide. ^{How 589}

In 1946, the first electronic digital computer, ENIAC (Electronic Numerical Integrator and Computer), was dedicated at the Moore School of Electrical Engineering at the University of Pennsylvania in Philadelphia, PA.   It was invented by Dr. John W. Mauchley and J. Presper Eckert, Jr.   It had 18,000 vacuum tubes, occupied an area 30 x 60 feet, and weighed 30 tons. ^{Carruth 531}

1950-1959

In 1951, Mauchley and Eckert introduce the UNIVAC for commercial use. ^{Carruth 553}

1960-1969

1970-1979

Ed Roberts of Albuquerque, NM, president of a small electronics company called MITS, in January 1975, using an Intel 8080 CPU, which sells as a kit for under $400 and has the same computing capability of $20,000- to $50,000-computers, advertises the Altair 8800 on the cover of Popular Electronics.   Expecting to sell 400 computers the first year, the company receives more than 1500 orders, cash in advance, by the end of February.   The personal computer business has begun.   Altair was operated by a form of the BASIC programming language developed by Paul Allen and Bill Gates.   Running into cash flow problems by better marketed lookalike computers, , MITS is forced to sell to Pertec, a disk drive manufacturer. ^{PC n.p.}

1980-1989

1990-1999