Re: OT

[Van Snyder <van.snyder@sbcglobal.net>]

On Thu, 2026-07-30 at 23:18 +0200, Jan Claeys wrote:

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.

Mauchly's ENIAC patent was invalidated citing ABC as prior art, mostly because he had visited Atanasoff at Iowa State and expressed amazement at the accomplishment of an electronic ALU.

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.