The Z2 was a mechanical and relay computer created by Konrad Zuse in 1939. It was an improvement on the Z1, using the same mechanical memory but replacing the arithmetic and control logic with electrical relay circuits. Photographs and plans for the Z2 were destroyed by allied bombardment during World War II. In contrast to the Z1, the Z2 used 16 bit fixed point arithmetic instead of 22 bit floating point.
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