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The History And Future Of Computers Essay

, Research Paper

The History and Future of Computers

Tim Gash

CRS-07

Mr. Drohan

January 31, 1997

With the advances in computer technology it is now possible for more and

more Canadians to have personal computers in their homes. With breakthroughs in

computer processing speeds and with computer storage capacity, the combination

of this with the reduced size of the computer have allowed for even the smallest

apartment to hold a computer. In the past the only places to have computers

were military institutes and some universities; this was because of their

immense size and price. Today with falling computer prices and the opportunity

to access larger networks, the amount of computers has grown from just 10% in

1986 to 25% in 1994. Also, of the 25%, 34% of them were equipped with modems,

which allow for connection to on line services via telephone lines.

The primitive start of the computer came about around 4000 BC; with the

invention of the abacus, by the Chinese. It was a rack with beads strung on

wires that could be moved to make calculations. The first digital computer is

usually accredited to Blaise Pascal. In 1642 he made the device to aid his

father, who was a tax collector. In 1694 Gottfried Leibniz improved the machine

so that with the rearrangement of a few parts it could be used to multiply. The

next logical advance came from Thomas of Colmar in 1890, who produced a machine

that could perform all of the four basic operations, addition, subtraction,

multiplication and division. With the added versatility this device was in

operation up until the First World War.

Thomas of Colmar made the common calculator, but the real start of

computers as they are known today comes from Charles Babbage. Babbage designed

a machine that he called a Difference Engine. It was designed to make many long

calculations automatically and print out the results. A working model was built

in 1822 and fabrication began in 1823. Babbage works on his invention for 10

years when he lost interest in it. His loss of interest was caused by a new idea

he thought up. The Difference Engine was limited in adaptability as well as

applicability. The new idea would be a general purpose, automatic mechanical

digital computer that would be fully program controlled. He called this the

Analytical Engine. It would have Conditional Control Transfer Capability so

that commands could be inputted in any order, not just the way that it had been

programmed. The machine was supposed to use punch cards which were to be read

into the machine from several reading stations. The machine was supposed to

operate automatically by steam power and only require one person there to

operate it. Babbages machines were never completed for reasons such as, non-

precise machining techniques, the interest of few people and the steam power

required for the devices was not readily available.

The next advance in computing came from Herman Hollerith and James Powers.

They made devices that were able to read cards that information had been punched

into, automatically. This advance was a huge step, because it provided memory

storage capability. Companies such as IBM and Remington made improved versions

of the machine that lasted for over fifty years.

ENIAC which was thought up in 1942, was in use from 1946 to 1955. Thought

up by J. Presper Eckert and his associates. The computer was the first high-

speed digital computer and was one thousand times faster than its predecessor,

the relay computers. ENIAC was very bulky, taking up 1,800 square feet on the

floor and having 18,000 vacuum tubes. It was also very limited in

programmability, but it was very efficient in the programs that it had been

designed for.

In 1945 John von Neumann along with the University of Pennsylvania came up

with what is known as the stored-program technique. Also due to the increasing

speed of the computer subroutines needed to be repeated so that the computer

could be kept busy. It

would also be better if instructions to the computer could be changed

during a compution so that there would be a different outcome in the compution.

Neumann fulfilled these needs by creating a command that is called a conditional

control transfer. The conditional control transfer allows for program sequences

to be started and stopped at any time. Instruction programs were also stored

together so that they can be arithmetically changed just like data. This

generation of computers included ones using RAM, as well as the first

commercially available computers, EDVAC and UNIVAC. These computers used

punched-card or punched tape reading devices. Also some of the later ones were

only about the size of a grand piano and contained 2,500 electron tubes, which

was much smaller than ENIAC.

During the fifties and sixties the two most important advances were

magnetic core memory and the transistor. These discoveries increased RAM sizes

from 8,000 to 64,000 words in commercially available computers. The first

supercomputers were made with this new technology. During this period

successful commercial computers were made by Burroughs, IBM, Sperry-Rand,

Honeywell and Control Data. These computers could now have printers, disk

storage, tape storage, stored programs and memory operating systems. These

computers were usually owned by industry, government and private laboratories.

The next advance came in the form of a chip. Transistors and vacuum tubes

created vast amounts of heat and this damaged the delicate internal parts of the

computer. The heat problem was eliminated through quartz. The integrated

circuit made in 1958 consisted of three components placed on a silicon disc that

was made of quartz. As technology advanced more and more components were fit

onto indiviual chips and this resulted in smaller and smaller computers. There

was also an operating system created during this stage that allowed for many

programs to be run at once, with one central program that had the ability to

monitor and coordinate computer memory.




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