This book is rewriting the history of computer science, arguing that in reality Colossus - the giant computer built by the British secret service during World War II - preceded the ENIAC by two years. Colossus was built during the Second World War in the Government Code and Cypher School at Bletchley Park. Included here are pieces by ex-Wrens who actually work the machine, the scientist who pioneered the use of vacuum tubes in data processing, and leading authorities on code-breaking and computer science. A must read for anyone curious about the code-breaking or World War II espionage, Colossus offers interesting accounts of people in the world first giant computer, great grandfather of large computers used today by the CIA and National Security Agency.