History of Computers


Only once in a lifetime will a new invention come about to touch every
aspect of our lives. Such a device that changes the way we work, live, and play
is a special one, indeed. A machine that has done all this and more now exists
in nearly every business in the US and one out of every two households (Hall,
156). This incredible invention is the computer. The electronic computer has
been around for over a half-century, but its ancestors have been around for 2000
years. However, only in the last 40 years has it changed the American society.
From the first wooden abacus to the latest high-speed microprocessor, the
computer has changed nearly every aspect of people\'s lives for the better.
The very earliest existence of the modern day computer\'s ancestor is the
abacus. These date back to almost 2000 years ago. It is simply a wooden rack
holding parallel wires on which beads are strung. When these beads are moved
along the wire according to "programming" rules that the user must memorize, all
ordinary arithmetic operations can be performed (Soma, 14). The next innovation
in computers took place in 1694 when Blaise Pascal invented the first “digital
calculating machine”. It could only add numbers and they had to be entered by
turning dials. It was designed to help Pascal\'s father who was a tax collector
(Soma, 32).
In the early 1800\'s, a mathematics professor named Charles Babbage
designed an automatic calculation machine. It was steam powered and could store
up to 1000 50-digit numbers. Built in to his machine were operations that
included everything a modern general-purpose computer would need. It was
programmed by--and stored data on--cards with holes punched in them,
appropriately called “punchcards”. His inventions were failures for the most
part because of the lack of precision machining techniques used at the time and
the lack of demand for such a device (Soma, 46).
After Babbage, people began to lose interest in computers. However,
between 1850 and 1900 there were great advances in mathematics and physics that
began to rekindle the interest (Osborne, 45). Many of these new advances
involved complex calculations and formulas that were very time consuming for
human calculation. The first major use for a computer in the US was during the
1890 census. Two men, Herman Hollerith and James Powers, developed a new
punched-card system that could automatically read information on cards without
human intervention (Gulliver, 82). Since the population of the US was
increasing so fast, the computer was an essential tool in tabulating the totals.
These advantages were noted by commercial industries and soon led to the
development of improved punch-card business-machine systems by International
Business Machines (IBM), Remington-Rand, Burroughs, and other corporations. By
modern standards the punched-card machines were slow, typically processing from
50 to 250 cards per minute, with each card holding up to 80 digits. At the time,
however, punched cards were an enormous step forward; they provided a means of
input, output, and memory storage on a massive scale. For more than 50 years
following their first use, punched-card machines did the bulk of the world\'s
business computing and a good portion of the computing work in science (Chposky,
73).
By the late 1930s punched-card machine techniques had become so well
established and reliable that Howard Hathaway Aiken, in collaboration with
engineers at IBM, undertook construction of a large automatic digital computer
based on standard IBM electromechanical parts. Aiken\'s machine, called the
Harvard Mark I, handled 23-digit numbers and could perform all four arithmetic
operations. Also, it had special built-in programs to handle logarithms and
trigonometric functions. The Mark I was controlled from prepunched paper tape.
Output was by card punch and electric typewriter. It was slow, requiring 3 to 5
seconds for a multiplication, but it was fully automatic and could complete long
computations without human intervention (Chposky, 103).
The outbreak of World War II produced a desperate need for computing
capability, especially for the military. New weapons systems were produced
which needed trajectory tables and other essential data.
In 1942, John P. Eckert, John W. Mauchley, and their associates at the
University of Pennsylvania decided to build a high-speed electronic computer to
do the job. This machine became known as ENIAC, for "Electrical Numerical
Integrator And Calculator". It could multiply two numbers at the rate of 300
products per second, by finding the value of each product from a multiplication
table stored in its memory. ENIAC was thus about 1,000 times faster than the
previous generation of computers (Dolotta, 47).
ENIAC used 18,000 standard vacuum tubes, occupied 1800 square feet of
floor space, and used about 180,000 watts