The technology behind the computer revolution can be traced back to the most basic calculating devices such as the abacus. The first "calculators" were mechanical devices that used toothed gears and levers. These machines were large and cumbersome. Many were room-sized.
Wilhelm Schickard invented the first real calculating machine. His invention was followed by the works of Pascal, Leibnitz, Mueller, and Colmar. Each of these individuals furthered the technology of the mechanical calculating devices.
Charles Babbage was an important contributor to the computer revolution. Though he lived and worked in the 1800s, his ideas and inventions were far ahead of his time. Babbage conceived the "Analytical Engine." This machine would have been in the form of punch cards. This machine would have fit the modern definition of a computer if it had only contained a stored program concept.
After Babbage, the advent of mechanical memory led to the first fully programmable calculator. Both the calculator and the mechanical memory were completed by Konrad Zuse.
The first machine to fit the modern definition of the computer was the "Mark I" and was completed in 1948 at Manchester University.
