‘Stored program’ is where the debate is. Colossus was ‘programmable’ but the program was not a series of instructions executed in a sequence - it was a single data process executed on the input data against a set of stored registers.
replyDefinitely programmable, definitely capable of computing, but not a ‘stored program’ in the sense we know it today.
Having seen the replica, I noticed it has a long continuous tape loop. Was the program "stored" in the paper tape?
replyIt was the first programmable electronic digital computing machine, yes. Special-purpose computing machines had been around since the 1600's (where they were used as textile weaving machines I think).
replyAnd the “electronic” part is important. The Z3 predates in by 2 years and was a programmable digital computer, except it used electromechanical relays.
replyThe Z3 is arguably more programmable than colossus and it was proven to be Turing complete in its stock configuration. Though the Z3 lacked the ability to conditionally branch, so nobody realised it at the time.