A Brief History of Computers - Lesson 02

Ancient Times
In the beginning, man used his fingers and toes to perform simple computations such as addition and subtraction. Later, man realized that by using some objects to represent digits, it might be possible to perform computations beyond the limited scope of one’s own fingers and toes.

The first man-made computing device is the “Abacus” . In the Abacus, small beads are arranged on a series of vertical rods in a manner that by manipulating them, it is possible with some skill and practice, to make rapid calculations. Addition, subtraction, division and multiplication can be performed on a standard abacus. The abacus is still in use today byshopkeepers in East Asia and some parts of North America.

The Abacus

Besides the abacus, early man also invented numbering systems to enable him to easily handle numbers greater than 10. One such numbering system is the decimal numbering system, which is traceable to early Hindu-Arabic influence. This decimal system, with specific digits representing numbers from 0 to 9, came into general use in Europe and has survived ever since.

1600 – 1900
In 1642, Blaise Pascal, a French mathematician, invented an adding machine. The machine has adopted partly the principles of the abacus but did away with the use of the hand to move the beads or counters. Instead, Pascal used wheels to move counters.

Blaise Pascal

The principle of Pascal’s machine is still being used today, such as in the counters of tape recorders and odometers. Pascal’s machine was one of the first mechanical calculating machines.

In 1674, Gottfried Wilhelm Von Leibnitz made improvements on Pascal’s machine. With Leibnitz’s improvements, it was possible for the machine to divide and multiply as easily as it could add and subtract.

When the age of industrialization spread throughout Europe, new machines were invented to be used in agricultural and production sites. An invention that made profound changes in the history of industrialization was the mechanical loom invented by a Frenchman named Joseph Jacquard. With the use of cards punched with holes, it was possible for the Jacquard loom to weave fabrics in a variety of patterns.

The idea of using a punched card to store a predetermined pattern to be woven by the loom clicked in the mind of Charles Babbage, an English mathematician who lived in the nineteenth century. He foresaw a machine that could perform all mathematical calculations, store values in its memory and perform logical comparisons among values. He called it the Analytical Engine. Babbage’s analytical engine, however, was never built. The technology at that time
was not adequate for building Babbage’s dream because electronics was not yet known or even thought of.

Babbage’s Analytical Engine

Herman Hollerith adopted the punched card concept of Jacquard to devise a system to process census data. Census data were translated into a series of holes in a punched card to represent the digits and the letters of the alphabet. It was then passed through a machine with a series of electrical contacts, which were either turned off or on depending on the existence or nonexistence of holes in the punched cards. These different combinations of off/on situations
were recorded by the machine and represented a way of tabulating the results of the Census. The Code developed by Hollerith is called the Hollerith Code.

Hollerith’s machine was highly successful. It reduced the time by two thirds of the time it took to tabulate the result of the Census manually.

1900 – 1945
Howard Aiken of Harvard University thought that technology in 1937 was just right to implement Babbage’s concept. With the combined effort of his colleagues in Harvard and IBM, the Automatic Sequence Controlled Calculator was built in 1944 and it was called MARK I.

MARK I could perform division, multiplication, addition and subtraction in a specified sequence determined by the setting of the switches. MARK I used a typewriter connected to it or punched cards to output results. It contained more than three thousand electro-mechanical relays and weighed five tons. MARK I was used for 15 years.

1946 – 1960
The ENIAC (Electronic Numerical Integrator and Computer) was the first electronic digital computer. It was built in 1946 at the Moore School of Electrical Engineering of the University of Pennsylvania. The ENIAC had no moving parts. It was programmable and had the capability to store calculation steps. The ENIAC used vacuum tubes (about 18,000 in
number).

A computer using vacuum tube technology is referred to as a first-generation computer. The ENIAC could perform an addition in 0.2 millisecond. This means that the machine was capable of performing about 5,000 computations per second. The principal drawback of ENIAC was its size and processing ability. It occupied 1,500 square feet of floor space and could process only one program or problem at a time.

In the 1950s, Remington Rand manufactured the UNIVAC I (Universal Automatic Calculator). It could calculate at the rate of 10,000 additions per second. In 1957, the International Business Machine Corporation (IBM) developed IBM 704 which could perform 100,000 calculations per second.