Z3 or not Z3 that is the question.

Anyone who reads this blog regularly is probably aware of the fact that the history of computing has more than a passing interest for me. I should add that the history of computing is for me not just the history of the machine on which I am typing this post but covers the whole history of computing in the true meaning of the word i.e. the calculating with numbers starting with people cutting notches in bones tens of thousands of years in the past and going up to the present. This post however concerns the history of the modern computer as the machine with which you are reading this post.

Now as I have already pointed out in a post about Charles Babbage the question as to who invented the computer depends on how you define computer. Do you mean mechanical, electro-mechanical or electronic, special purpose or general purpose, programmable or not programmable, Turning complete or not, binary or decimal and so on and so forth. Beyond this list of technical problems it would appear that there is a certain national element involved in the answer to this question. If you visit the normally excellent Stanford Encyclopaedia of Philosophy and read the History of Modern Computing article you will find discussions of Babbage, Turing, Atanasoff and many others but you wont find a single word about Konrad Zuse who was born 100 years ago on 22^nd June 1910. Some of you might ask so what? The answer in really quite simple according to the Germans, and not only the Germans, Konrad Zuse invented the computer.

Konrad Zuge 1992 Source: Wikimedia Commons

Konrad Zuse was a German engineer who built his first machine the Z1, a mechanical computer, in 1938. Built with massive steel components that Zuse cut out with a jigsaw the Z1 was never very reliable and Zuse transferred his concept to the Z2 a prototype that functioned with electrical relays in 1939. This he developed further and produced his Z3 in 1941. This was a fully programmable, binary, Turing complete general purpose electro-mechanical computer. Apart from the fact that it was electro-mechanical and not electronic Zuse’s Z3 was in every aspect a modern computer. Unfortunately for him the Z3 was destroyed in an air raid so after the war the honours for inventing the computer went to Eckert’s and Mauchly’s ENIAC although later an American judge in a strange ruling awarded this honour to Atanasoff and Berry, strange because the ABC never actually functioned.

Reconstruction of Zuse Z3 im Deutschen Museum in München Source: Wikimedia Commons

After WW II Zuse built his first electronic computer the Z4 and this went into production, my university here in Erlangen had a Z4 as its first computer and it’s still here in their museum of computing and is still functioning. Today Zuse is generally recognised as the inventor of the computer for his Z3 but apparently not in America.