A HISTORICAL OVERVIEW OF THE COMPUTER
CONTENTS
1. Introduction
2. Objectives
3. Main Content
3.i A Brief History of Computer Technology
3.ii First Generation Electronic Computers (1937-1953)
3.iii Second Generation (1954-1972)
3.iv Third Generation (1903-1972)
3.v Fourth Generation (1972-1984)
3.vi Fifth Generation (1984-1990)
3.vii Sixth Generation (1990-Date)
4. Conclusion
5. Summary
INTRODUCTION
The computer as we know it today has evolved over the ages. An attempt is made in this unit to present
in chronological order the various landmarks and milestones in the development of the computer. Based
on the milestone achievement of each era, the computer evolution is categorised into generations. The
generational classification, however, is not rigid as we may find one generation eating into the next.
OBJECTIVES
At the end of this unit you should be able to:
explain the processes leading to the emergence of the modern computer
predict the direction of research in computer technology in the near future.
3.0 MAIN CONTENT
A BRIEF HISTORY OF COMPUTER TECHNOLOGY
A complete history of computing would include a multitude of diverse devices such as the ancient
Chinese abacus, the Jacquard loom (1805) and Charles Babbage’s “analytical engine” (1834). It would
also
include a discussion of mechanical, analog and digital computing architectures. As late as the 1960s,
mechanical devices, such as the Merchant calculator, still found widespread application in science and
engineering. During the early days of electronic computing devices, there was much discussion about
the relative merits of analog vs. digital computers. In fact, as late as the 1960s, analog computers were
, routinely used to solve systems of finite difference equations arising in oil reservoir modeling. In the
end, digital computing devices proved to have the power, economics and scalability necessary to deal
with large scale computations. Digital computers now dominate the computing world in all areas ranging
from the hand calculator to the supercomputer and are pervasive throughout society. Therefore, this
brief sketch of the development of scientific computing is limited to the area of digital, electronic
computers.
The evolution of digital computing is often divided into generations. Each generation is characterised by
dramatic improvements over the previous generation in the technology used to build computers, the
internal organisation of computer systems, and programming languages. Although not usually
associated with computer generations, there has been a steady improvement in algorithms, including
algorithms used in computational science. The following history has been organised using these widely
recognized generations as mileposts.
FIRST GENERATION ELECTRONIC COMPUTERS (1937 – 1953)
Three machines have been promoted at various times as the first electronic computers. These machines
used electronic switches, in the form of vacuum tubes, instead of electromechanical relays. In principle
the electronic switches were more reliable, since they would have no moving parts that would wear out,
but technology was still new at that time and the tubes were comparable to relays in reliability.
Electronic components had one major benefit, however: they could “open” and “close” about 1,000
times faster than mechanical switches.
The earliest attempt to build an electronic computer was by J. V. Atanasoff, a professor of physics and
mathematics at Iowa State, in 1937. Atanasoff set out to build a machine that would help his graduate
students solve systems of partial differential equations. By 1941, he and graduate student Clifford Berry
had succeeded in building a machine that could solve 29 simultaneous equations with 29 unknowns.
However, the machine was not programmable, and was more of an electronic calculator.
A second early electronic machine was Colossus, designed by Alan Turning for the British military in
1943. This machine played an
important role in breaking codes used by the German army in World War II. Turning’s main contribution
to the field of computer science was the idea of the Turning Machine, a mathematical formalism widely
used in the study of computable functions. The existence of Colossus was kept secret until long after the
war ended, and the credit due to Turning and his colleagues for designing one of the first working
electronic computers was slow in coming.
The first general purposes programmable electronic computer was the Electronic Numerical Integrator
and Computer (ENIAC), built by J. Presper Eckert and John V. Mauchly at the University of Pennsylvania.
Work began in 1943, funded by the Army Ordinance Department, which needed a way to compute
ballistics during World War II. The machine wasn’t completed until 1945, but then it was used
extensively for calculations during the design of the hydrogen bomb. By the time it was decommissioned
CONTENTS
1. Introduction
2. Objectives
3. Main Content
3.i A Brief History of Computer Technology
3.ii First Generation Electronic Computers (1937-1953)
3.iii Second Generation (1954-1972)
3.iv Third Generation (1903-1972)
3.v Fourth Generation (1972-1984)
3.vi Fifth Generation (1984-1990)
3.vii Sixth Generation (1990-Date)
4. Conclusion
5. Summary
INTRODUCTION
The computer as we know it today has evolved over the ages. An attempt is made in this unit to present
in chronological order the various landmarks and milestones in the development of the computer. Based
on the milestone achievement of each era, the computer evolution is categorised into generations. The
generational classification, however, is not rigid as we may find one generation eating into the next.
OBJECTIVES
At the end of this unit you should be able to:
explain the processes leading to the emergence of the modern computer
predict the direction of research in computer technology in the near future.
3.0 MAIN CONTENT
A BRIEF HISTORY OF COMPUTER TECHNOLOGY
A complete history of computing would include a multitude of diverse devices such as the ancient
Chinese abacus, the Jacquard loom (1805) and Charles Babbage’s “analytical engine” (1834). It would
also
include a discussion of mechanical, analog and digital computing architectures. As late as the 1960s,
mechanical devices, such as the Merchant calculator, still found widespread application in science and
engineering. During the early days of electronic computing devices, there was much discussion about
the relative merits of analog vs. digital computers. In fact, as late as the 1960s, analog computers were
, routinely used to solve systems of finite difference equations arising in oil reservoir modeling. In the
end, digital computing devices proved to have the power, economics and scalability necessary to deal
with large scale computations. Digital computers now dominate the computing world in all areas ranging
from the hand calculator to the supercomputer and are pervasive throughout society. Therefore, this
brief sketch of the development of scientific computing is limited to the area of digital, electronic
computers.
The evolution of digital computing is often divided into generations. Each generation is characterised by
dramatic improvements over the previous generation in the technology used to build computers, the
internal organisation of computer systems, and programming languages. Although not usually
associated with computer generations, there has been a steady improvement in algorithms, including
algorithms used in computational science. The following history has been organised using these widely
recognized generations as mileposts.
FIRST GENERATION ELECTRONIC COMPUTERS (1937 – 1953)
Three machines have been promoted at various times as the first electronic computers. These machines
used electronic switches, in the form of vacuum tubes, instead of electromechanical relays. In principle
the electronic switches were more reliable, since they would have no moving parts that would wear out,
but technology was still new at that time and the tubes were comparable to relays in reliability.
Electronic components had one major benefit, however: they could “open” and “close” about 1,000
times faster than mechanical switches.
The earliest attempt to build an electronic computer was by J. V. Atanasoff, a professor of physics and
mathematics at Iowa State, in 1937. Atanasoff set out to build a machine that would help his graduate
students solve systems of partial differential equations. By 1941, he and graduate student Clifford Berry
had succeeded in building a machine that could solve 29 simultaneous equations with 29 unknowns.
However, the machine was not programmable, and was more of an electronic calculator.
A second early electronic machine was Colossus, designed by Alan Turning for the British military in
1943. This machine played an
important role in breaking codes used by the German army in World War II. Turning’s main contribution
to the field of computer science was the idea of the Turning Machine, a mathematical formalism widely
used in the study of computable functions. The existence of Colossus was kept secret until long after the
war ended, and the credit due to Turning and his colleagues for designing one of the first working
electronic computers was slow in coming.
The first general purposes programmable electronic computer was the Electronic Numerical Integrator
and Computer (ENIAC), built by J. Presper Eckert and John V. Mauchly at the University of Pennsylvania.
Work began in 1943, funded by the Army Ordinance Department, which needed a way to compute
ballistics during World War II. The machine wasn’t completed until 1945, but then it was used
extensively for calculations during the design of the hydrogen bomb. By the time it was decommissioned
