ABC

In 1939, John Vincent Atansoff and Clifford Berry, Atanasoff's graduate student, built the ABC computer at Iowa State college. The Atanasoff Berry Computer, later named the ABC, was an early digital computer that had the capacity to store data in binary form and had electronic logic circuits to perfrom addition and subtraction, specifically designed to solve linear equations. Once Atanasoff and Berry had built the prototype for their computer, they designed and constructed the larger, more general-purpose computer now commonly recognized as the ABC. This basic computer was the world's first electronic digital computer and gave the basis of all computers: using a binary system of arithmetic, separate memory and comptuing functions, regenerative memory, and more common factors used today in computers. Unfortunately, the original was destroyed in a fire, but Iowa State University rebuilt the ABC computer and can now be seen there.