Timeline of Computer History

The Atanasoff-Berry Computer

The Atanasoff-Berry Computer (ABC) is completed

After successfully demonstrating a proof-of-concept prototype in 1939, Professor John Vincent Atanasoff receives funds to build a full-scale machine at Iowa State College (now University). The machine was designed and built by Atanasoff and graduate student Clifford Berry between 1939 and 1942. The ABC was at the center of a patent dispute related to the invention of the computer, which was resolved in 1973 when it was shown that ENIAC co-designer John Mauchly had seen the ABC shortly after it became functional.

The legal result was a landmark: Atanasoff was declared the originator of several basic computer ideas, but the computer as a concept was declared un-patentable and thus freely open to all. A full-scale working replica of the ABC was completed in 1997, proving that the ABC machine functioned as Atanasoff had claimed. The replica is currently on display at the Computer History Museum.

Operator at Complex Number Calculator (CNC)

The Complex Number Calculator (CNC) is completed

ERA 1101

ERA 1101 introduced

Close up shot of Apollo Guidance Computer read-only rope memory

Apollo Guidance Computer read-only rope memory

TX-0 at MIT

MIT researchers build the TX-0

Microsoft Word 1.1 screenshot

Microsoft introduces Word