Public knowledge

The Z3 and Colossus were developed independently of each other and independently from the ABC and the ENIAC during World War II. The Z3 was destroyed by Allied bombing of Berlin in 1943. The Colossus machines were part of the UK's war effort, and were destroyed in 1945 to maintain secrecy. Their existence only became generally known in the 1970s, though knowledge of their capabilities remained among their UK staff and invited Americans. The ABC was dismantled by Iowa State University, after John Atanasoff was called to Washington, D.C. to do physics research for the U.S. Navy. ENIAC, by contrast, was put through its paces for the press in 1946, "and captured the world's imagination".^[20]

Older histories of computing may therefore not be comprehensive in their coverage and analysis of this period.