Реферат: Computers History And Development Essay Research Paper

Computers: History And Development Essay, Research Paper


Nothing epitomizes modern life better

than the computer. For better or worse, computers have infiltrated every

aspect of our society. Today computers do much more than simply compute:

supermarket scanners calculate our grocery bill while keeping store inventory;

computerized telphone switching centers play traffic cop to millions of

calls and keep lines of communication untangled; and automatic teller machines

(ATM) let us conduct banking transactions from virtually anywhere in the

world. But where did all this technology come from and where is it heading?

To fully understand and appreciate the impact computers have on our lives

and promises they hold for the future, it is important to understand their


Early Computing Machines and Inventors

The abacus,

which emerged about 5,000 years ago in Asia Minor and is still in use

today, may be considered the first computer. This device allows users

to make computations using a system of sliding beads arranged on a rack.

Early merchants used the abacus to keep trading transactions. But as the

use of paper and pencil spread, particularly in Europe, the abacus lost

its importance. It took nearly 12 centuries, however, for the next significant

advance in computing devices to emerge. In 1642, Blaise

Pascal (1623-1662), the 18-year-old son of a French tax collector,

invented what he called a numerical wheel calculator to help his father

with his duties. This brass rectangular box, also called a Pascaline,

used eight movable dials to add sums up to eight figures long. Pascal’s

device used a base of ten to accomplish this. For example, as one dial

moved ten notches, or one complete revolution, it moved the next dial

– which represented the ten’s column – one place. When the ten’s dial

moved one revolution, the dial representing the hundred’s place moved

one notch and so on. The drawback to the Pascaline, of course, was its

limitation to addition.

In 1694, a German mathematician and philosopher, Gottfried

Wilhem von Leibniz (1646-1716), improved the Pascaline by creating

a machine that could also multiply. Like its predecessor, Leibniz’s mechanical

multiplier worked by a system of gears and dials. Partly by studying Pascal’s

original notes and drawings, Leibniz was able to refine his machine. The

centerpiece of the machine was its stepped-drum gear design, which offered

an elongated version of the simple flat gear. It wasn’t until 1820, however,

that mechanical calculators gained widespread use. Charles Xavier Thomas

de Colmar, a Frenchman, invented a machine that could perform the four

basic arithmetic functions. Colmar’s mechanical calculator, the arithometer,

presented a more practical approach to computing because it could add,

subtract, multiply and divide. With its enhanced versatility, the arithometer

was widely used up until the First World War. Although later inventors

refined Colmar’s calculator, together with fellow inventors Pascal and

Leibniz, he helped define the age of mechanical computation.

The real beginnings of computers as we know them today, however, lay

with an English mathematics professor, Charles

Babbage (1791-1871). Frustrated at the many errors he found while

examining calculations for the Royal Astronomical Society, Babbage declared,

«I wish to God these calculations had been performed by steam!»

With those words, the automation of computers had begun. By 1812, Babbage

noticed a natural harmony between machines and mathematics: machines were

best at performing tasks repeatedly without mistake; while mathematics,

particularly the production of mathematic tables, often required the simple

repetition of steps. The problem centered on applying the ability of machines

to the needs of mathematics. Babbage’s first attempt at solving this problem

was in 1822 when he proposed a machine to perform differential equations,

called a Difference

Engine. Powered by steam and large as a locomotive, the machine would

have a stored program and could perform calculations and print the results

automatically. After working on the Difference Engine for 10 years, Babbage

was suddenly inspired to begin work on the first general-purpose computer,

which he called the Analytical Engine. Babbage’s assistant, Augusta

Ada King, Countess of Lovelace (1815-1842) and daughter of English

poet Lord Byron,

was instrumental in the machine’s design. One of the few people who understood

the Engine’s design as well as Babbage, she helped revise plans, secure

funding from the British government, and communicate the specifics of

the Analytical Engine to the public. Also, Lady Lovelace’s fine understanding

of the machine allowed her to create the instruction routines to be fed

into the computer, making her the first female computer programmer. In

the 1980’s, the U.S. Defense Department

named a programming language ADA

in her honor.

Babbage’s steam-powered Engine, although ultimately never constructed,

may seem primitive by today’s standards. However, it outlined the basic

elements of a modern general purpose computer and was a breakthrough concept.

Consisting of over 50,000 components, the basic design of the Analytical

Engine included input devices in the form of perforated cards containing

operating instructions and a «store» for memory of 1,000 numbers

of up to 50 decimal digits long. It also contained a «mill»

with a control unit that allowed processing instructions in any sequence,

and output devices to produce printed results. Babbage borrowed the idea

of punch cards to encode the machine’s instructions from the Jacquard

loom. The loom, produced in 1820 and named after its inventor, Joseph-Marie

Jacquard, used punched boards that controlled the patterns to be woven.

In 1889, an American inventor,

Herman Hollerith (1860-1929), also applied the Jacquard loom concept

to computing. His first task was to find a faster way to compute the U.S.

census. The previous census in 1880 had taken nearly seven years to

count and with an expanding population, the bureau feared it would take

10 years to count the latest census. Unlike Babbage’s idea of using perforated

cards to instruct the machine, Hollerith’s method used cards to store

data information which he fed into a machine that compiled the results

mechanically. Each punch on a card represented one number, and combinations

of two punches represented one letter. As many as 80 variables could be

stored on a single card. Instead of ten years, census takers compiled

their results in just six weeks with Hollerith’s machine. In addition

to their speed, the punch cards served as a storage method for data and

they helped reduce computational errors. Hollerith brought his punch card

reader into the business world, founding Tabulating Machine Company in

1896, later to become International Business

Machines (IBM) in 1924 after a series of mergers. Other companies

such as Remington

Rand and Burroghs also manufactured punch readers for business use.

Both business and government used punch cards for data processing until

the 1960’s.

In the ensuing years, several engineers made other significant advances.



(1890-1974) developed a calculator for solving differential equations

in 1931. The machine could solve complex differential equations that had

long left scientists and mathematicians baffled. The machine was cumbersome

because hundreds of gears and shafts were required to represent numbers

and their various relationships to each other. To eliminate this bulkiness,

John V. Atanasoff

(b. 1903), a professor at Iowa State College (now called Iowa

State University) and his graduate student, Clifford Berry,

envisioned an all-electronic computer that applied Boolean algebra to

computer circuitry. This approach was based on the mid-19th century work

of George Boole (1815-1864) who clarified the

binary system of algebra, which stated that any mathematical equations

could be stated simply as either true or false. By extending this concept

to electronic circuits in the form of on or off, Atanasoff and Berry had

developed the first all-electronic computer by 1940. Their project, however,

lost its funding and their work was overshadowed by similar developments

by other scientists.

Five Generations of Modern Computers

First Generation (1945-1956)

With the onset of the Second

World War, governments sought to develop computers to exploit their

potential strategic importance. This increased funding for computer development

projects hastened technical progress. By 1941 German engineer Konrad

Zuse had developed a computer, the Z3, to design airplanes

and missiles. The Allied forces, however, made greater strides in developing

powerful computers. In 1943, the British completed a secret code-breaking

computer called Colossus

to decode German

messages. The Colossus’s impact on the development of the computer

industry was rather limited for two important reasons. First, Colossus

was not a general-purpose computer; it was only designed to decode secret

messages. Second, the existence of the machine was kept secret until decades

after the war.

American efforts produced a broader achievement. Howard H. Aiken (1900-1973),

a Harvard engineer working with IBM, succeeded in producing an all-electronic

calculator by 1944. The purpose of the computer was to create ballistic

charts for the U.S. Navy. It was about

half as long as a football field and contained about 500 miles of wiring.

The Harvard-IBM Automatic Sequence Controlled Calculator, or Mark I for

short, was a electronic relay computer. It used electromagnetic signals

to move mechanical parts. The machine was slow (taking 3-5 seconds per

calculation) and inflexible (in that sequences of calculations could not

change); but it could perform basic arithmetic as well as more complex


Another computer development spurred by the war was the Electronic Numerical

Integrator and Computer (ENIAC),

produced by a partnership between the U.S. government and the University

of Pennsylvania. Consisting of 18,000 vacuum tubes, 70,000 resistors

and 5 million soldered joints, the computer was such a massive piece of

machinery that it consumed 160 kilowatts of electrical power, enough energy

to dim the lights in an entire section of Philadelphia.

Developed by John

Presper Eckert (1919-1995) and John W. Mauchly (1907-1980),

ENIAC, unlike the Colossus and Mark I, was a general-purpose computer

that computed at speeds 1,000 times faster than Mark I.

In the mid-1940’s John

von Neumann (1903-1957) joined the University of Pennsylvania team,

initiating concepts in computer design that remained central to computer

engineering for the next 40 years. Von Neumann designed the Electronic

Discrete Variable Automatic Computer (EDVAC)

in 1945 with a memory to hold both a stored program as well as data. This

«stored memory» technique as well as the «conditional control

transfer,» that allowed the computer to be stopped at any point and

then resumed, allowed for greater versatility in computer programming.

The key element to the von Neumann architecture was the central processing

unit, which allowed all computer functions to be coordinated through a

single source. In 1951, the UNIVAC

I (Universal Automatic Computer), built by Remington Rand, became

one of the first commercially available computers to take advantage of

these advances. Both the U.S. Census

Bureau and General Electric owned

UNIVACs. One of UNIVAC’s impressive early achievements was predicting

the winner of the 1952 presidential election, Dwight

D. Eisenhower.


generation computers were characterized by the fact that operating instructions

were made-to-order for the specific task for which the computer was to

be used. Each computer had a different binary-coded program called a machine

language that told it how to operate. This made the computer difficult

to program and limited its versatility and speed. Other distinctive features

of first generation computers were the use of vacuum

tubes (responsible for their breathtaking size) and magnetic drums

for data storage.


Generation Computers (1956-1963)


1948, the invention of the transistor greatly

changed the computer’s development. The transistor replaced the large,

cumbersome vacuum tube in televisions, radios and computers. As a result,

the size of electronic machinery has been shrinking ever since. The transistor

was at work in the computer by 1956. Coupled with early advances in magnetic-core

memory, transistors led to second generation computers that were smaller,

faster, more reliable and more energy-efficient than their predecessors.

The first large-scale machines to take advantage of this transistor technology

were early supercomputers, Stretch by IBM and LARC by Sperry-Rand. These

computers, both developed for atomic energy laboratories, could handle

an enormous amount of data, a capability much in demand by atomic scientists.

The machines were costly, however, and tended to be too powerful for the

business sector’s computing needs, thereby limiting their attractiveness.

Only two LARCs were ever installed: one in the Lawrence

Radiation Labs in Livermore, California, for which the computer was

named (Livermore Atomic Research Computer) and the other at the U.S.

Navy Research and Development Center in Washington,

D.C. Second generation computers replaced machine language with assembly

language, allowing abbreviated programming codes to replace long, difficult

binary codes.

Throughout the early 1960’s, there were a number of commercially successful

second generation computers used in business, universities, and government

from companies such as Burroughs, Control

Data, Honeywell, IBM, Sperry-Rand,

and others. These second generation computers were also of solid state

design, and contained transistors in place of vacuum tubes. They also

contained all the components we associate with the modern day computer:

printers, tape storage, disk storage, memory, operating systems, and stored

programs. One important example was the IBM 1401, which was universally

accepted throughout industry, and is considered by many to be the Model

T of the computer industry. By 1965, most large business routinely processed

financial information using second generation computers.

It was the stored program and programming language that gave computers

the flexibility to finally be cost effective and productive for business

use. The stored program concept meant that instructions to run a computer

for a specific function (known as a program) were held inside the computer’s

memory, and could quickly be replaced by a different set of instructions

for a different function. A computer could print customer invoices and

minutes later design products or calculate paychecks. More sophisticated

high-level languages such as COBOL

(Common Business-Oriented Language) and FORTRAN

(Formula Translator) came into common use during this time, and have expanded

to the current day. These languages replaced cryptic binary machine code

with words, sentences, and mathematical formulas, making it much easier

to program a computer. New types of careers (programmer, analyst, and

computer systems expert) and the entire software

industry began with second generation computers.

Third Generation Computers (1964-1971)

Though transistors were clearly an improvement over the vacuum tube,

they still generated a great deal of heat, which damaged the computer’s

sensitive internal parts. The quartz rock eliminated this problem.

Jack Kilby, an engineer with Texas

Instruments, developed the integrated circuit (IC) in 1958. The IC

combined three electronic components onto a small silicon disc, which

was made from quartz. Scientists later managed to fit even more components

on a single chip, called a semiconductor. As a result, computers became

ever smaller as more components were squeezed onto the chip. Another third-generation

development included the use of an operating

system that allowed machines to run many different programs at once

with a central program that monitored and coordinated the computer’s memory.

Fourth Generation (1971-Present)

After the integrated circuits, the only place to go was down – in size,

that is. Large scale integration (LSI) could fit hundreds of components

onto one chip. By the 1980’s, very large scale integration (VLSI) squeezed

hundreds of thousands of components onto a chip. Ultra-large scale integration

(ULSI) increased that number into the millions. The ability to fit so

much onto an area about half the size of a U.S. dime helped diminish the

size and price of computers. It also increased their power, efficiency

and reliability. The Intel 4004 chip,

developed in 1971, took the integrated circuit one step further by locating

all the components of a computer (central processing unit, memory, and

input and output controls) on a minuscule chip. Whereas previously the

integrated circuit had had to be manufactured to fit a special purpose,

now one microprocessor could be manufactured and then programmed to meet

any number of demands. Soon everyday household items such as

microwave ovens, television sets and automobiles

with electronic fuel injection

incorporated microprocessors.

Such condensed power allowed everyday people to harness a computer’s

power. They were no longer developed exclusively for large business or

government contracts. By the mid-1970’s, computer manufacturers sought

to bring computers to general consumers. These minicomputers came complete

with user-friendly software packages that offered even non-technical users

an array of applications, most popularly word processing and spreadsheet

programs. Pioneers in this field were Commodore,

Radio Shack and Apple

Computers. In the early 1980’s, arcade

video games such as Pac Man and

home video game systems such as the

Atari 2600 ignited consumer interest for more sophisticated, programmable

home computers.

In 1981, IBM introduced its personal computer (PC) for use in the home,

office and schools. The 1980’s saw an expansion in computer use in all

three arenas as clones of the IBM PC made the personal computer even more

affordable. The number of personal computers in use more than doubled

from 2 million in 1981 to 5.5 million in 1982. Ten years later, 65 million

PCs were being used. Computers continued their trend toward a smaller

size, working their way down from desktop to laptop computers (which could

fit inside a briefcase) to palmtop (able to fit inside a breast pocket).

In direct competition with IBM’s PC was Apple’s Macintosh line, introduced

in 1984. Notable for its user-friendly design, the Macintosh offered an

operating system that allowed users to move screen icons instead of typing

instructions. Users controlled the screen cursor using a mouse, a device

that mimicked the movement of one’s hand on the computer screen.

As computers became more widespread in the workplace, new ways to harness

their potential developed. As smaller computers became more powerful,

they could be linked together, or networked, to share memory space, software,

information and communicate with each other. As opposed to a mainframe

computer, which was one powerful computer that shared time with many terminals

for many applications, networked computers allowed individual computers

to form electronic co-ops. Using either direct wiring, called a Local

Area Network (LAN), or telephone lines, these networks could reach

enormous proportions. A global web of computer circuitry, the Internet,

for example, links computers worldwide into a single network of information.

During the 1992 U.S. presidential election, vice-presidential candidate

Al Gore

promised to make the development of this so-called «information superhighway»

an administrative priority. Though the possibilities envisioned by Gore

and others for such a large network are often years (if not decades) away

from realization, the most popular use today for computer networks such

as the Internet is electronic mail, or E-mail, which allows users to type

in a computer address and send messages through networked terminals across

the office or across the world.

Fifth Generation (Present and Beyond)

Defining the fifth generation of computers is somewhat difficult because

the field is in its infancy. The most famous example of a fifth generation

computer is the fictional HAL9000

from Arthur

C. Clarke’s novel, 2001: A

Space Odyssey. HAL performed all of the functions currently

envisioned for real-life fifth generation computers. With artificial

intelligence, HAL could reason well enough to hold conversations with

its human operators, use visual input, and learn from its own experiences.

(Unfortunately, HAL was a little too human and had a psychotic breakdown,

commandeering a spaceship and killing most humans on board.)

Though the wayward HAL9000 may be far from the reach of real-life computer

designers, many of its functions are not. Using recent engineering advances,

computers are able to accept spoken

word instructions (voice recognition) and imitate human reasoning.

The ability to translate a foreign language is also moderately possible

with fifth generation computers. This feat seemed a simple objective at

first, but appeared much more difficult when programmers realized that

human understanding relies as much on context and meaning as it does on

the simple translation of words.

Many advances in the science of computer design and technology are coming

together to enable the creation of fifth-generation computers. Two such

engineering advances are parallel processing, which replaces von Neumann’s

single central processing unit design with a system harnessing the power

of many CPUs to work as one. Another advance is superconductor

technology, which allows the flow of electricity with little or no resistance,

greatly improving the speed of information flow. Computers today have

some attributes of fifth generation computers. For example, expert systems

assist doctors in making diagnoses by applying the problem-solving steps

a doctor might use in assessing a patient’s needs. It will take several

more years of development before expert systems are in widespread use.



Timothy Trainor and Diane Trainor


The Smithsonian Book of Information Age Inventions, Steven Lubar.

Houghton Mifflin Company, 1993.


Turing: The Enigma Andrew Hodges, 1983. Simon & Schuster,

New York.


Great,» Steven Levy. Popular Science, February, 1994.


Wonder,» Joseph Nocera. GQ, October, 1993.


Apple’s Uncertain Future,» MacWorld, October, 1993.


For Change,» Michael Myer. Newsweek, August 29, 1994.


Games,» James K. Willcox. Popular Mechanics, December,



Worlds Without End,» Keith Ferrell, Omni, October 1993.


Big Brother,» David Sheff. Rolling Stone, January 9, 1992.


PC Week Stat Sheet: A Decade of Computing,» PC Week. February

28, 1994.


Commodore, 1954-1994,» Tom R. Halfhill. Byte, August,



Catch Up…» Jim Carlton, Wall Street Journal October

17, 1994.


to the Computer Age, Harry Wulforst


Early Computers, Charles J. Bashe, Lyle R. Johnson, John H. Palmer,

Emerson Pugh.


Computer Comes of Age, R. Moreau


Computer Pioneers, David Ritchie


The Rise and Fall of Atari, Scott Cohen


Grolier’s Encyclopedia, Grolier Electronic Publishing, Inc.

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