Computer Geniuses

Computer Geniuses

From the earliest times the need to carry out calculations has been developing. The first steps
involved the development of counting and calculation aids such as the counting board and the
abacus.

Pascal(1623-62) was the son of a tax collector and a mathematical genius. He designed the first
mechanical calculator (Pascaline) based on gears. It performed addition and subtraction.
Leibnitz (1646-1716) was a German mathematician and built the first calculator to do
multiplication and division. It was not reliable due to accuracy of contemporary parts.

Babbage (1792-1872) was a British inventor who designed an ‘analytical engine’ incorporating
the ideas of a memory and card input/ouput for data and instructions. Again the current
technology did not permit the complete construction of the machine.

Babbage is largely remembered because of the work of Augusta Ada (Countess of Lovelace) who
was probably the first computer programmer.
Burroughs (1855-98) introduced the first commercially successful mechanical adding machine of
which a million were sold.by 1926.

Hollerith developed an electromechanical punched-card tabulator to tabulate the data for 1890
U.S. census. Data was entered on punched cards and could be sorted according to the census
requirements. The machine was powered by electricity. He formed the Tabulating Machine
Company which became International Business Machines (IBM). IBM is still one of the
largest computer companies in the world.

Aiken (1900-73) a Harvard professor with the backing of IBM built the Harvard Mark I
computer (51ft long) in 1944. It was based on relays (operate in milliseconds) as opposed to the
use of gears. It required 3 seconds for a multiplication.

Eckert and Mauchly designed and built the ENIAC in 1946 for military computations. It used
vacuum tubes (valves) which were completely electronic (operated in microseconds) as opposed
to the relay which was electromechanical.

It weighed 30 tons, used 18000 valves, and required 140 kwatts of power. It was 1000 times
faster than the Mark I multiplying in 3 milliseconds. ENIAC was a decimal machine and could
not be programmed without altering its setup manually.

Atanasoff had built a specialised computer in 1941 and was visited by Mauchly before the
construction of the ENIAC. He sued Mauchly in a case which was decided in his favour in 1974!
Von Neumann was a scientific genius and was a consultant on the ENIAC project. He
formulated plans with Mauchly and Eckert for a new computer (EDVAC) which was to store
programs as well as data.

This is called the stored program concept and Von Neumann is credited with it. Almost all
modern computers are based on this idea and are referred to as von neumann machines.
He also concluded that the binary system was more suitable for computers since switches have
only two values. He went on to design his own computer at Princeton which was a general
purpose machine.

Alan Turing was a British mathematician who also made significant contributions to the early
development of computing, especially to the theory of computation. He developed an abstract
theoretical model of a computer called a Turing machine which is used to capture the notion of
computable i.e. what problems can and what problems cannot be computed. Not all problems
can be solved on a computer.

Note: A Turing machine is an abstract model and not a physical computer.
From the 1950’s, the computer age took off in full force. The years since then have been divided
into periods or generations based on the technology used.