The purpose, origins, and design of the world's first programmable digital electronic computer.

Descriptions of the Lorenz cipher machine and the Colossus computer built to crack the code. Information on the rebuild of a working Colossus.

History and photos.

Information and photos on the Colossus rebuild project at Bletchley Park.

Brief description and photos.

Brief description and photo.

Article from the American Computer Science Association about the history of Colossus (and IBM's involvement in WWII).