A series of mainframe computers produced by Unisys when they were still Sperry Corporation.

The Series 1100 bravely went where (almost) nobody else did, with a 36 bit word format. The advantage over the more conventional format of 32 bits is that one word was large enough to hold all instructions, complete with modifiers such as indirection and index incrementation flags, and 16 to 18 bits worth of address or constant data information.

Hardware-wise, the 1100s were based on emitter coupled logic (ECL).

These machines were popular with airlines, banks and other outfits with the need to process large amounts of data quickly. Some places that I know of which used Series 1100s are: The University of Maryland, the University of Karlsruhe, the Schweizer Bankgesellschaft, Otto-Versand Hamburg, and Lufthansa.

After Sperry became Unisys, this series was renamed to Unisys 2200.