It is interesting to know that the term 'computer' was assigned to people's job which consisted of performing calculations on a continuous basis, like navigational tables, tide charts, and planetary positions for astronomical needs.
Human errors, boredom and comparatively slow pace of working, led inventors to mechanize the entire process and eventually come up with machines that had brains - computers! Need for accurate and fast calculations led to the invention of tools like Napier's bones for logarithms, the slide rule, calculating clock, Pascal's Pascaline, and power-loom that used punched cards; which can be considered as the forefathers of today's computers.
Talking about the history and evolution of computers, will be incomplete without the mention of Charles Babbage, who is considered the 'Father of Computers'. He was making a steam-driven calculating machine, the size of a room, way back in 1822, which he called the 'Difference Engine'.
The Difference Engine
The Difference Engine project, though heavily funded by the British government, could never see the light of the day. Yet, in pursuit of a better machine for more complex calculations, he came up with the 'Analytical Engine' that had parts parallel to the memory card and the central processing unit that our systems have today. Hollerith desk was later invented in the U.S. For the need to record the census in 1880, which used a combination of the earlier calculating tools that were invented.
In the 1940s there were attempts to make machines that served the purpose of computing numbers and problems, like the Z1 Computer in 1936.
Then Konrad Zuse also wanted to make something that would be like a computer, hence was created electromechanical "Z machines," the Z3, in 1941, which was the first working machine, which featured binary arithmetic, including floating point arithmetic and a measure of programmability. Zuse also started the first computer start-up company, which was established in 1946.
The ABC or Atanasoff-Berry Computer in 1942, Harvard Mark I Computer in 1944 also contributed to the evolution of computers that we know them today. It was not before the ENIAC that the public got its first feel of computers.
ENIAC / Electronic Numerical Integrator And Computer
The Birth of ENIAC
It was during World War II that the need for computing artillery firing tables for the United States Army's Ballistic Research Laboratory arose, which gave birth to the giant electronic brain - ENIAC. When the design and construction for this machine was financed by the United States Army, and the contract was signed on June 5, 1943; work progressed secretly in the University of Pennsylvania Moore School of Electrical Engineering, under the name 'Project PX'.
Renaming of ENIAC
Three years of dedicated work by John Mauchly, J. Presper Eckert and their team towards making of ENIAC finally tasted success when it was announced to the public on February 14, 1946; which was formally accepted by the Army in July 1946. ENIAC was, however, shut down on November 9, 1946 for up-gradation and started again on July 29, 1947. It was operational until October 2, 1955. It was renamed as IEEE Milestone in 1987.
Properties of ENIAC
ENIAC was massive in its physical size if you compare it to modern PCs. It contained approximately 17,468 vacuum tubes, 7,200 crystal diodes, 1,500 relays, 70,000 resistors, 10,000 capacitors and around 5 million hand-soldered joints, which weighed about 30 short tons (27 t). It consumed around 150 kW of power. ENIAC was reliable, programmable, though not as easy and user-friendly as the modern-day computers.
First Ever Desktop Computer
The first desktop-sized computer system, designed specifically for personal use, was launched in 1974 by Micro Instrumentation Telemetry Systems (MITS). This first computer was called Altair, which started selling with an overwhelming response for little less than $400.
Many entrepreneurial firms smelled the market demand for such computers and started producing and selling these machines. Tandy Corporation (RadioShack) was the first major electronics firm to manufacture and sell personal computers in 1977 that had features like a keyboard and a cathode-ray display terminal (CRT).
Introduction of "Apple" to The World
In 1976, Steve Jobs and Steve Wozniak started working on the homemade microprocessor computer board, Apple I. In early 1977, both formed a company called Apple Computer, Inc. and introduced the world to the first personal computer - Apple II which was complete with keyboard and color graphics capability.