Heath Robinson was a machine used by British codebreakers at the Government Code and Cypher School (GC&CS) at Bletchley Park during World War II in Cryptanalysis of the Lorenz cipher. This achieved the decryption of messages in the German teleprinter cipher produced by the Lorenz SZ40/42 in-line cipher machine. Both the cipher and the machines were called "Tunny" by the codebreakers, who named different German teleprinter ciphers after fish.