Helmut Schreyer

Helmut Theodor Schreyer (1912 to 1984) was a German inventor and electrical engineer best known for his contributions to the Z3, generally regarded as the world's first programmable computer. Working with Konrad Zuse in Berlin, Schreyer proposed using vacuum tube and relay based electronic circuits for calculating machines and demonstrated the approach to a small audience in 1938, theoretical work that fed into the Z3's design. He studied at the Technische Universitat Berlin and later held both German and Brazilian citizenship, dying in Rio de Janeiro.