The first electronic digital computer was the Atanasoff–Berry Computer (ABC), begun in 1937 and largely completed by around 1942 at Iowa State College in the United States. It was designed by physicist John Vincent Atanasoff with his graduate student Clifford Berry to solve systems of linear equations using binary arithmetic and vacuum tubes.

However, “first digital computer” can mean different things, and historians sometimes highlight other milestones:

  • Charles Babbage is credited with conceiving the first automatic digital computer in the 1830s with his (never completed) Analytical Engine.
  • Konrad Zuse’s Z3 (completed in 1941) is often cited as the first working, programmable digital electromechanical computer.
  • ENIAC (announced in 1946) is famous as an early general‑purpose electronic digital computer, though later court rulings emphasized that its core ideas drew on Atanasoff’s earlier work on the ABC.

So, in short:

  • If you mean the first electronic digital computer actually built: the Atanasoff–Berry Computer, invented by John Vincent Atanasoff (with Clifford Berry) around 1939–1942.
  • If you mean the first concept of an automatic digital computer: Charles Babbage’s Analytical Engine in the 1830s.