| Bletchley Park in north Buckinghamshire was the principal Allied centre for codebreaking. |
| The role of the Post Office research laboratories at Dollis Hill, London, played a key role in the codebreaking activities at Bletchley Park, which was one of the origins of the first computers. |
| The codebreaking work at Bletchley is estimated to have shortened the second world war by two years and saved thousands of lives. |
| The principal characters in this drama are not the giant computers used for storage, analysis and codebreaking, or the technicians who built them. |
| The Lorenz SZ40 messages were unlocked by two spectacular pieces of codebreaking. |
| Working in Hut 8 at Bletchley Park, then the home of GCHQ's forerunner, the Government Code and Cypher School, Turing found a way of reading messages sent by the Germans, using a codebreaking machine called the bombe. |
