IBM 709 definition computer
A computer made by IBM
oriented toward scientific work. The 709 had the same basic architecture as the IBM 704
but with many I/O
and performance refinements over the 704.
The IBM 709 (like the 704) had 36-bit memory words, 15-bit addresses and instructions with one address. A few index register
instructions had the infamous 15-bit decrement field in addition to the 15-bit address.
The IBM 7090
was a transistorised version of the 709.
[Difference between 704 and 709?]