COMPUTER THE BEGINNING

Bell Laboratories scientist George Stibitz uses relays for a demonstration adder

Called the “Model K” Adder because he built it on his “Kitchen” table, this simple demonstration circuit provides proof of concept for applying Boolean logic to the design of computers, resulting in construction of the relay-based Model I Complex Calculator in 1939. That same year in Germany, engineer Konrad Zuse built his Z2 computer, also using telephone company relays.

Konrad Zuse finishes the Z3 Computer

The Z3, an early computer built by German engineer Konrad Zuse working in complete isolation from developments elsewhere, uses 2,300 relays, performs floating point binary arithmetic, and has a 22-bit word length. The Z3 was used for aerodynamic calculations but was destroyed in a bombing raid on Berlin in late 1943. Zuse later supervised a reconstruction of the Z3 in the 1960s, which is currently on display at the Deutsches Museum in Munich.

The first Bombe is completed

Built as an electromechanical mechanical means of decrypting Nazi ENIGMA-based military communications during World War II, the British Bombe is conceived of by computer pioneer Alan Turing and Harold Keen of the British Tabulating Machine Company. Hundreds of bombes were built, their purpose to ascertain the daily rotor start positions of Enigma cipher machines, which in turn allowed the Allies to decrypt German messages.