The first digital computer
Source: Computer Hope
Short for Atanasoff-Berry Computer, the ABC began development by Professor John Vincent Atanasoff and graduate student Cliff Berry in 1937. Its development continued until 1942 at the Iowa State College (now Iowa State University).
The ABC was an electrical computer that used more than 300 vacuum tubes for digital computation, including binary math and Boolean logic and had no CPU (was not programmable). On October 19, 1973, US Federal Judge Earl R. Larson signed his decision that the ENIAC patent by J. Presper Eckert and John Mauchly was invalid. In the decision, Larson named Atanasoff the sole inventor.
The ENIAC was invented by J. Presper Eckert and John Mauchly at the University of Pennsylvania and began construction in 1943 and was not completed until 1946. It occupied about 1,800 square feet and used about 18,000 vacuum tubes, weighing almost 50 tons. Although the Judge ruled that the ABC computer was the first digital computer, many still consider the ENIAC to be the first digital computer because it was fully functional.