The G1 and the Gottingen family of digital computers

A small group under the direction of Dr. Heinz Billing constructed four different computers, the G1 (1952), the G2 (1955), the Gla (1958) and the G3 (1961), at the Max Planck Institute in Gottingen. The G1, G2 and Gla were bit-serial machines, which used a magnetic drum for both the main memory and the bit-serial registers. Whereas the G1 and Gla used punched tape programming, the G2 was controlled by stored programs. The G3 was a bit-parallel computer with a ferrite core memory of 4096 50-bit words for numbers and programs, and which operated at a speed of 5000 Flops. The G1 and G2 operated using fixed-point arithmetic, whereas the Gla and G3 had a floating-point arithmetic unit. Each of the G-computers was in operation on a regular basis at the Institute for several years.