Colossus was a set of computers developed by British codebreakers in the years 1943–1945 to help in the cryptanalysis of the Lorenz cipher. Colossus used thermionic valves to perform Boolean and counting operations. Colossus is regarded as the world's first programmable, electronic, digital computer. The first electromechanical computer was Konrad Zuse's Z3, completed in Berlin in 1941.