IBM 701

The 701 was first delivered in 1952. It was IBM's first "mass produced" stored program computer. While other computing devices had been built, they were either not stored program (e.g., the 604 calculator, or various accounting machines built previously with programs stored on wiring boards instead of in memory) or were not mass produced (e.g, the Selective Sequence Electronic Calculator, or SSEC, completed in 1948).

Only 19 701's were built, but the experience paved the way for subsequent mass produced computers.

Click on the link below for a view of The Gallery's 701-type pluggable unit (PU). PU's were electronic component assemblies that could be swapped out more easily and quickly than individual components could be.

Below is a comparison of pluggable units. The small single (or sometimes double) vacuum tube units were used on the 604 calculator and other equipment. The 8-tube unit is of the type used in the 701. The large PU is from the SAGE computer installation at McCord AFB, Washington.