b. Increased Speed. Early transistors were only 1/200th the size of the bulky
vacuum tubes. Because of this, an electric impulse had a shorter distance to travel
within it and was, therefore, much faster than a vacuum tube.
c. Reduced Heat and Increased Reliability. Vacuum tubes gave off so much
heat that, despite air conditioning, the heat generated affected the reliability of the
machines. Since the transistor was a solid one-piece unit, it was far more rugged and
reliable and produced much less heat.
1-20. THIRD-GENERATION INTEGRATED CIRCUIT COMPUTERS (1964)
Third-generation computers, introduced in 1964, made use of microelectronic or
integrated circuits on a large scale. This technology compressed hundreds of
thousands of transistor circuits into minute silicon microchips. A single silicon
microchip, smaller than a baby's fingernail, could hold hundreds of thousands of
electronic components. Microchips and other advances resulted in expanded speed,
efficiency, and memory capability.
integrated circuit: electronic circuit whose components are etched on a single
piece of semiconductor material, usually a silicon chip, less than 1/8 inch
square; permits faster, cheaper processing than with transistors.
Section V. REVIEW
1-21. MANUAL PHASE
a. Computing and record-keeping devices used increasingly as people
organized into tribes and began engaging in commerce.
b. Earliest manual aids to memory: fingers, stones, sticks, scratches on a rock,
knots in a string.
c. Early manual data processing (facts recorded for later use and manipulation),
circa 3000 BC.
(1)
Cuneiform, clay tablets used by Babylonian merchants.
(2) Papyrus scrolls, paper-like parchment used by Egyptians to inscribe
hieroglyphics.
d. The abacus: the most important early computing device known. It was widely
used since 2000 BC, .and is still used a lot in the Orient.
MD0057
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