Lecture 2

History Of Computer
1. Earliest Computing Devices
(a) Abacus
 considered as the 1st manual data processing device
 developed in China in 12th century A.D.
 performs arithmetic calculations
(b) Napier’s Bones
 developed by a Scottish mathematician John Napier
 obtain products & quotients of large numbers
(c) Ougthred’s Slide Rule
 invented by William Ougthred in 17th century
 arithmetic operations could be done by simply sliding the rulers
(d) Pascal’s Calculator
 developed by a French mathematician Blaise Pascal in 1645
 could add & subtract numbers up to 8 digits

(e) Leibniz Calculator

 invented by Gottfried Leibniz in 1694
 it utilized the same techniques for addition & subtraction as Pascal’s device but could also
perform multiplication, division & square root
(f) Babbage Analytical Engine
 designed to use 2 types of cards: operation cards & variable cards
 developed by Charles Babbage, the Father of Modern Computer. It is not because of the
machine he build but rather his ideas became the basis for modern computation devices
 * Lady Ada Byron, worked w/ Babbage & considered as the First Programmer

(g) Hollerith’s Punched – Card Machine

 developed by a statistician named Herman Hollerith in 1880
 considered as the 1st commercially successful data processing machine.
 * Hollerith made a census machine used by the US Bureau of Census in 1890

The history of computing began with an analog machine. In 1623 German scientist Wilhelm Schikard
invented a machine that used 11 complete and 6 incomplete sprocketed wheels that could add, and with the aid of
logarithm tables, multiply and divide.

      French philosopher, mathematician, and physicist Blaise Pascal invented a machine in 1642 that added and
subtracted, automatically carrying and borrowing digits from column to column. Pascal built 50 copies of his
machine, but most served as curiosities in parlors of the wealthy. Seventeenth-century German mathematician
Gottfried Leibniz designed a special gearing system to enable multiplication on Pascal’s machine.

      Computer Card Key Punch The IBM 010 punch was one of the first devices designed to perforate cards. A hole
or the lack of a hole in a card represented information that could be read by early computers. Modern optical storage
devices, such as CD-ROMs, use microscopic pits instead of punched paper holes to store information. THE
BETTMANN ARCHIVE/Corbis 

      In the early 19th century French inventor Joseph-Marie Jacquard devised a specialized type of computer: a silk
loom. Jacquard’s loom used punched cards to program patterns that helped the loom create woven fabrics. Although
Jacquard was rewarded and admired by French emperor Napoleon I for his work, he fled for his life from the city of
Lyon pursued by weavers who feared their jobs were in jeopardy due to Jacquard’s invention. The loom prevailed,
however: When Jacquard died, more than 30,000 of his looms existed in Lyon. The looms are still used today,
especially in the manufacture of fine furniture fabrics.

      American physicist John Atanasoff built the first rudimentary electronic computer in the late 1930s and early
1940s, although for several decades afterward credit for the first electronic computer went to the scientists who
assembled the Electronic Numerical Integrator and Computer (ENIAC) for the United States military in 1945.
Danish physicist Allan Mackintosh recounts in a Scientific American article how Atanasoff first conceived of the
design principles that are still used in present-day computers.

      Another early mechanical computer was the Difference Engine, designed in the early 1820s by British
mathematician and scientist Charles Babbage. Although never completed by Babbage, the Difference Engine was
intended to be a machine with a 20-decimal capacity that could solve mathematical problems. Babbage also made
plans for another machine, the Analytical Engine, considered the mechanical precursor of the modern computer. The
Analytical Engine was designed to perform all arithmetic operations efficiently; however, Babbage’s lack of
political skills kept him from obtaining the approval and funds to build it.

      Augusta Ada Byron, countess of Lovelace, was a personal friend and student of Babbage. She was the daughter
of the famous poet Lord Byron and one of only a few woman mathematicians of her time. She prepared extensive
notes concerning Babbage’s ideas and the Analytical Engine. Lovelace’s conceptual programs for the machine led to
the naming of a programming language (Ada) in her honor. Although the Analytical Engine was never built, its key
concepts, such as the capacity to store instructions, the use of punched cards as a primitive memory, and the ability
to print, can be found in many modern computers.

ACCORDING TO AGE AND COMPONENT GENERATIONS

FIRST GENERATION COMPUTERS (1951 – 1958)
COMPONENT : Employed a vacuum tubes in the electronic circuitry to control internal
operations.
SIZE : The sizes were very large and requiring a lot of space.
RELIABILITY : Poor reliability due to the components employed which is frequently
overheated and burned out.
STORAGE CAPACITY : Memory capacity was approximately 200 to 3000 characters, which is quite
small compared with preset day computers.
COST : Relatively high cost for given capacity.
PROCESSING SPEED : Operating speed was in milliseconds (one thousandth of a second)
POWER REQUIREMENTS : Required considerable power to run including special air conditioning to
get rid of tube-generated heat.
SOFTWARE DEVELOPMENT : Computer instructions were performed in internal codes of machines,
requiring extensive knowledge of the machine. Low level/Symbolic
language programming.
HARDWARE DEVELOPMENT : The introduction of UNIVAC I marked the beginning of the first generation
Computer.
OTHERS : Magnetic drum as primary internal storage medium. Punched card oriented.
Dr. Grace Hopper saw the original bug. A moth caused the operation of a
 computer to stop and from then on, any computer problem or programming
mistake was called a bug.

SECOND GENERATION COMPUTERS (1959 – 1964)

COMPONENT : Introduction of transistors as a machine component replacing vacuum
tubes.
SIZE : The sizes were reduced s compared to the first generation.
RELIABILITY : More reliable than predecessor which greatly reduced heat generated
during operations.
STORAGE CAPACITY : Memory capacity was approximately 30, 000 characters.
COST : Components used reduced overall cost of maintaining one binary digit of
storage.
PROCESSING SPEED : Operating speed was in microseconds (one millionth of a second)
POWER REQUIREMENTS : Power requirement was further educed.
SOFTWARE DEVELOPMENT : Programs made use of symbolic languages requiring the use of translators.
Introduction and wide acceptance of high-level languages such as
FORTRAN and COBOL. Which were machine-dependent; negate the
requirements of comprehensive knowledge of computers.
HARDWARE DEVELOPMENT : The mainframes introduced were IBM 1400 series and IBM 7000 series,
Honeywell 2 200, CDC 1604, Control Data 3600 and General Electric
635.
OTHERS : Magnetic core as primary internal storage medium. Magnetic tape
oriented. Batch oriented applications. Introduction of real time processing.

THIRD GENERATION COMPUTERS (1965 – 1970)

COMPONENT : Integrated circuits (ICs) replaced the transistors of the second generation
although microscopic in size contained the equivalent or many transistors.
SIZE : Smaller in size led to the emergence of minicomputers which had smaller
word size, 16 compared to 32 bits.
RELIABILITY : Improved reliability and low voltage requirement.
STORAGE CAPACITY : Storage capacity further increased to 500, 000 characters of min storage.
COST : Cost of storage further decreased per binary digit.
PROCESSING SPEED : Operating speed was in nanoseconds (one billionth of a second)
POWER REQUIREMENTS : Power required for operation was also further reduced.
SOFTWARE DEVELOPMENT : Availability of operating systems programs to control I/O and do many
 tasks previously handled by human operators. Extensive use of high level
programming languages.
HARDWARE DEVELOPMENT : Introduction of minicomputers; computers of this era were much smaller
than their predecessors but only slightly less capable. (Ex. are IBM S/360,
NCR395, and Burroughs B6500)
OTHERS : Magnetic core as solid-state main storage. Magnetic disk oriented. Remote
processing and time-sharing. Beginning of Data Communications
Technology.

FOURTH GENERATION COMPUTERS (1970 – 1980’S)

COMPONENT : Made use of Medium Scale Integration (MSI) and Large Scale Integrated
circuits (LSI). Hundreds of circuits were placed in a chip size of a pinhead.
Circuitry density in IC’s is referred to by level of integration. Complete
circuits were reduced to virtually microscopic sizes.
SIZE : Smaller in size led to the emergence of minicomputers which had smaller
word size, 16 compared to 32 bits.
RELIABILITY : Further improvement in reliability.
STORAGE CAPACITY : Further increase in storage capacity.
COST : Further reduction in cost, internal storage costs decreasing per binary digit.
Reduction in extensive site preparation cost and space requirements
needed for computer systems.
PROCESSING SPEED : Since computer were reduced in size, the distance for the power to travel
were reduced a hundred times shorter.
POWER REQUIREMENTS : Decrease in power utilization.
SOFTWARE DEVELOPMENT : Availability of sophisticated programs for special applications like the
Computer Aided Instructions (CAI) and the mathematical modeling and
simulation.
HARDWARE DEVELOPMENT : Introduction of microprocessors, microcomputers (APPLE) and home
computers. Due to utilization of microscopic sized elements, computers of
this generation were of desk to top size. Ex. IBM 3033, HP 3000.
OTHERS : Greater versatility of I/O devices. Modular design and compatibility
between hardware equipment provided by different manufacturers
(customers are no longer tied to one vendor)

FIFTH GENERATION COMPUTERS

 Not yet been formally defined
 Make use of technologies such as Very Large Integration (VSI), Grand Scale Integration (GSI), optical
devices, parallel processing, magnetic bubble memories and Josephson junctions (a switching component).
 Supercomputers were envisioned as ultra fast, ultra small with minimal electricity requirements and will
exhibit some measure of artificial intelligence.