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A Brief History of the Computer


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Title: A Brief History of the Computer

A Brief History of the Computer
  • Presented by
  • Trisha Cummings

What is a Computer?
  • A computer is a machine which can take
    instructions, and perform computations based on
    those instructions
  • It is the ability to take instructions often
    known as programs in computer speak and
    execute them, is what distinguishes a computer
    from a mechanical calculator.

Numbers, Calculating and Us
  • The first known use of numbers dates back to
    around 30000 BC when tally marks were used by
    Paleolithic peoples.
  • It is safe to assume that humans begin counting -
    and that fingers and thumbs provide nature's
  • The decimal system is no accident.
  • Ten has been the basis of most counting systems
    in history. When any sort of record is needed,
    notches in a stick or a stone are the natural
  • This system had no concept of place-value (such
    as in the currently used decimal notation), which
    limited its representation of large numbers.
  • Egyptian numbers 3000-1600 BC
  • In Egypt, from about 3000 BC, records survive in
    which 1 is represented by a vertical line and 10
    is shown as .
  • The Egyptians write from right to left, so the
    number 23 becomes lll

Babylonian numbers 1750 BC
  • The Babylonians use a numerical system with 60 as
    its base.
  • This is extremely unwieldy, since it should
    logically require a different sign for every
    number up to 59 (.
  • Instead, numbers below 60 are expressed in
    clusters of ten - making the written figures
    awkward for any arithmetical computation.
  • Through the Babylonian pre-eminence in astronomy,
    their base of 60 survives even today in the 60
    seconds and minutes of angular measurement, in
    the 180 degrees of a triangle and and in the 360
    degrees of a circle.
  • Much later, when time can be accurately measured,
    the same system is adopted for the subdivisions
    of an hour.
  • The Babylonians take one crucial step towards a
    more effective numerical system.
  • They introduce the place-value concept, by which
    the same digit has a different value according to
    its place in the sequence.
  • We now take for granted the strange fact that in
    the number 222 the digit '2' means three quite
    different things - 200, 20 and 2 - but this idea
    is new and bold in Babylon.

Zero, decimal system, Arabic numerals from 300 BC
  • The digits now used internationally make their
    appearance gradually from about the 3rd century
    BC, when some of them feature in the inscriptions
    of Asoka.
  • The Indians use a dot or small circle when the
    place in a number has no value, and they give
    this dot a Sanskrit name - sunya, meaning
  • The system has fully evolved by about AD 800,
    when it is adopted also in Baghdad.
  • The Arabs use the same 'empty' symbol of dot or
    circle, and they give it the equivalent Arabic
    name, sifr.
  • About two centuries later the Indian digits reach
    Europe in Arabic manuscripts, becoming known as
    Arabic numerals.
  • And the Arabic sifr is transformed into the
    'zero' of modern European languages.
  • But several more centuries must pass before the
    ten Arabic numerals gradually replace the system
    inherited in Europe from the Roman empire.

The abacus 1st millennium BC
  • In practical arithmetic the merchants have been
    far ahead of the scribes, for the idea of zero is
    in use in the market place long before its
    adoption in written systems.
  • It is an essential element in humanity's most
    basic counting machine, the abacus.
  • This method of calculation - originally simple
    furrows drawn on the ground, in which pebbles can
    be placed - is believed to have been used by
    Babylonians and Phoenicians from perhaps as early
    as 1000 BC.
  • In a later and more convenient form, still seen
    in many parts of the world today, the abacus
    consists of a frame in which the pebbles are kept
    in clear rows by being threaded on rods.
  • Zero is represented by any row with no pebble at
    the active end of the rod.

Roman numerals from the 3rd century BC
  • The completed decimal system is so effective that
    it becomes, eventually, the first example of a
    fully international method of communication.
  • But its progress towards this dominance is slow.
  • For more than a millennium the numerals most
    commonly used in Europe are those evolved in Rome
    from about the 3rd century BC.
  • They remain the standard system throughout the
    Middle Ages, reinforced by Rome's continuing
    position at the centre of western civilization
    and by the use of Latin as the scholarly and
    legal language.

Binary numbers 20th century AD/CE
  • Our own century has introduced another
    international language, which most of us use but
    few are aware of.
  • This is the binary language of computers.
  • When interpreting coded material by means of
    electricity, speed in tackling a simple task is
    easy to achieve and complexity merely
  • So the simplest possible counting system is best,
    and this means one with the lowest possible base
    - 2 rather than 10.
  • Instead of zero and 9 digits in the decimal
    system, the binary system only has zero and 1.
  • So the binary equivalent of 1, 2, 3, 4, 5, 6, 7,
    8, 9, 10 is 1, 10, 11, 100, 101, 111, 1000, 1001,
    1011, 1111 and so ad infinitum

Ancient Computer
  • A bronze Greek device constructed in around 80BC
    could be the world's oldest computer.
  • The "Antikythera Mechanism" - consisting more
    than 30 bronze dials and wheels - was recovered
    from the wreck of a cargo ship off the Greek
    island of Antikythera in 1900.
  • Its exact purpose was unknown, although a theory
    centers on it being used to calculate the
    movement of the planets then known to the Greeks
    Mercury, Venus, Mars, Jupiter and Saturn.

'Antikythera Mechanism'
Adding Machines
  • Adding machines date back to the 17th century.
  • They started with simple machines that could only
    add (and sometimes subtract.)
  • Many were rather tricky to use and could produce
    erroneous results with untrained users.
  • Apparently, Wilhelm Schickard produced the first
    adding machine in 1623.

  • Unfortunately, this one-of-kind machine was
    destroyed in a fire and its existence remained
    unknown until recently.
  • Blaise Pascal (re)invented an adding/subtracting
    machine in 1642 with no knowledge of Shickard's
  • Pascal made many of his machines and is therefore
    often thought of as the original inventor.
  • His first machine was 14" x 5" x 3" and had 8

Jacquard Loom
  • Basile Bouchon was a textile worker in Lyon who
    invented a way to control a loom with a
    perforated paper tape in 1725.
  • The son of an organ maker, Bouchon adapted the
    concept of music automata controlled by pegged
    cylinders to the repetitive task of weaving.
  • Further refinements by others eventually lead to
    the wildly successful Jacquard loom.

  • Jacques de Vaucanson (February 24, 1709November
    21, 1782) was a French engineer and inventor who
    is credited with creating the world's first true
    robots, as well as for creating the first
    completely automated loom.
  • His proposals for the automation of the weaving
    process, although ignored during his lifetime,
    were later perfected and implemented by Joseph
    Marie Jacquard, the creator of the Jacquard loom.

  • The Jacquard Loom is a mechanical loom, invented
    by Joseph Marie Jacquard in 1801, that has holes
    punched in pasteboard, each row of which
    corresponds to one row of the design.
  • Multiple rows of holes are punched on each card
    and the many cards that compose the design of the
    textile are strung together in order.

  • Uses punch card technology
  • on a treadle driven loom

Charles Babbage
  • Perhaps the most famous mechanical computer was
    Charles Babbage's Analytical Engine, first
    proposed in the 1830's.
  • He originated the idea of a programmable
  • Considered the "father of computing."
  • Invents Analytical machine an automatic
    calculator which never makes it off the ground
    due to its complexity (1823 1842)

  • Nine years later, the Science Museum completed
    the printer Babbage had designed for the
    difference engine, an astonishingly complex
    device for the 19th century.
  • Parts of his uncompleted mechanisms are on
    display in the London Science Museum.
  • In 1991 a perfectly functioning difference
    engine was constructed from Babbage's original
  • Built to tolerances achievable in the 19th
    century, the success of the finished engine
    indicated that Babbage's machine would have

Difference Engine
  • Charles Babbage

Herman Hollerith
  • Is widely regarded as the father of modern
    automatic computation.
  • He chose the punched card as the basis for
    storing and processing information and he built
    the first punched-card tabulating and sorting
    machines as well as the first key punch, and he
    founded Tabulating Machine Company.
  • Which later becomes IBM.
  • Hollerith's designs dominated the computing
    landscape for almost 100 years.

  • Hollerith's ideas for automation of the census
    are expressed succinctly in Patent No. 395,782 of
    Jan. 8, 1889
  • "The herein described method of compiling
    statistics which consists in recording separate
    statistical items pertaining to the individual by
    holes or combinations of holed punched in sheets
    of electrically non-conducting material, and
    bearing a specific relation to each other and to
    a standard, and then counting or tallying such
    statistical items separately or in combination by
    means of mechanical counters operated by
    electro-magnets the circuits through which are
    controlled by the perforated sheets,
    substantially as and for the purpose set forth."

  • Had the idea to use Jacquard's punched cards to
    represent the census data, and to then read and
    collate this data using an automatic tabulating

How it works
  • The results of a tabulation are displayed on the
    clock-like dials.
  • A sorter is on the right.
  • On the tabletop below the dials are a
    Pantographic card punch on left and the card
    reading station on the right, in which metal pins
    pass through the holes, making contact with
    little wells of mercury, completing an electrical
  • When workers wanted some time off, they would
    suck the mercury out of the wells with medicine
    droppers and squirt it into the spittoon).
  • All of these devices are fed manually, one card
    at a time, but the tabulator and sorter are
    electrically coupled.

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  • He did not stop at his original 1890 tabulating
    machine and sorter, but produced many other
    innovative new models.
  • He also invented the first automatic card-feed
    mechanism, the first key punch, and took what was
    perhaps the first step towards programming by
    introducing a wiring panel in his 1906 Type I
    Tabulator, allowing it to do different jobs
    without having to be rebuilt!
  • The 1890 Tabulator was hardwired to operate only
    on 1890 Census cards.
  • These inventions were the foundation of the
    modern information processing industry.

Hollerith Automatic Feed Tabulator
  • After the 1890 census, the US population
    continued to grow and the original
    tabulator-sorters were not fast enough to handle
    the 1900 census so Hollerith devised another
    machine to stave off another data processing
  • Towards the end of the 1900 Census, Hollerith
    sped up the processing of information by adding
    an automatic feed to his tabulator.
  • It fed cards downward into the unit through a
    circuit-closing press.
  • Later, the pins of the sensing unit were replaced
    by brushes to further speed the flow of
    information and information punched in the cards
    began to control the operation of the units.
  • Hollerith had begun to put information on the
    assembly line.

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Pantographic Card Punch
  • Developed for the 1890 US census.
  • Prior to 1890, cards were punched using a train
    conductor's ticket punch that allowed holes to be
    placed only around the edge of the card, and was
    not terribly accurate, and which tended to induce
    strain injuries.
  • The Pantographic punch allowed accurate placement
    of holes with minimum physical strain, one hole
    at a time, and also provided access to the
    interior of the card, allowing more information
    per card.

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Our First Real Computer Eniac
  • ENIAC, short for Electronic Numerical Integrator
    And Computer
  • It was the first high-speed, purely electronic,
    digital computer capable of being reprogrammed to
    solve a full range of computing problems
  • ENIAC was conceived and designed by John Mauchly
    and J. Presper Eckert of the University of
  • ENIAC was designed and built to calculate
    artillery firing tables for the U.S. Army's
    Ballistic Research Laboratory

  • The contract was signed on June 5, 1943.
  • In July, 1943 was constructed by the University
    of Pennsylvania's Moore School of Electrical
  • It was unveiled on February 14, 1946, having cost
    almost 500,000.
  • ENIAC was shut down on November 9, 1946 for a
    refurbishment and a memory upgrade, and was
    transferred to Aberdeen Proving Ground, Maryland
    in 1947.
  • There, on July 29 of that year, it was turned on
    and ran continuous until 1145 p.m. October 2,

  • ENIAC's physical size was massive compared to
    modern PC standards.
  • It weighed 30 short tons, was roughly 8.5 feet by
    3 feet by 80 feet, took up 680 square feet
  • Basically, it filled an entire room.
  • It used vacuum tube technology
  • It contained 17,468 vacuum tubes, 7,200 crystal
    diodes, 1,500 relays, 70,000 resistors, 10,000

Six women did most of the programming of
ENIAC by manipulating its switches and cables
Two women wiring the right side of the ENIAC with
a new program. "U.S. Army Photo" from the
archives of the ARL Technical Library. Standing
Ester Gerston Crouching Gloria Ruth Gorden
Cpl. Irwin Goldstein (sets the switches on one of
the ENIAC's function tables at the Moore School
of Electrical Engineering. (U.S. Army photo)
  • Programmers Betty Jean Jennings (left) and Fran
    Bilas (right) operate the ENIAC's main control
    panel at the Moore School of Electrical
    Engineering. (U.S. Army photo from the archives
    of the ARL Technical Library)

J. Presper Eckert and John W. Mauchly examine a
printout of ENIAC results in a newsreel from
February 1946.
Glen Beck (background) and Betty Snyder
(foreground) program the ENIAC in BRL building
328. (U.S. Army photo)
  • UNIVAC I of 1951 was the first business computer
    made in the U.S. "Many people saw a computer for
    the first time on television when UNIVAC I
    predicted the outcome of the 1952 presidential
  • Bendix G-15 of 1956, inexpensive at 60,000, for
    science and industry but could also be used by a
    single user several hundred were built - used
    magnetic tape drive and key punch terminal

  • IBM 650 that "became the most popular
    medium-sized computer in America in the 1950's" -
    rental cost was 5000 per month - 1500 were
    installed - able to read punched cards or
    magnetic tape - used rotating magnetic drum main
    memory unit that could store 4000 words,
  • Jack Kilby of Texas Instruments patented the
    first integrated circuit in Feb. 1959
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