On Thu, 2026-07-30 at 14:02 -0700, Van Snyder wrote: > On Thu, 2026-07-30 at 22:56 +0200, Jan Claeys wrote: > > On Thu, 2026-07-30 at 14:51 -0400, hlyg wrote: > > > 1st computer ENIAC was built in US in 1945 > > > > Correction: Konrad Zuse finished his Z4 computer in April 1945, > > before ENIAC was finished in May 1945. > > > > And before that there were also programmable computers in several > > countries that weren’t “potentially universal Turing machines” yet, > > including Zuse’s Z1 in 1938, Zuse’s Z3 in 1941, the UK’s Colossus > > in 1943, and the Harvard Mark I in 1944, etc. > > How about the ABC, or Atanasoff-Berry Computer at Iowa State in 1937- > 1942?
It was the first to do computations electronically (with vacuum tubes) instead of electro-mechanically (with relays) or mechanically (e.g. Charles Babbage’s Analytical Engine, or Zuse’s Z1), but it wasn’t programmable. Basically it was the ALU part of a modern CPU, but lacking the part that interprets an instruction set. Zuse original design plan for the Z3 was also to use vacuum tubes, and he demonstrated a small prototype, but he couldn’t get access to the thousands of vacuum tubes needed, so his further designs until (way) after World War II all used mechanical relays instead. -- Jan Claeys (please don't CC me when replying to the list)
