Stepping Switch from Colossus Mark II

1944, UK

I Hooked the Big Tuna.

I may be small, but I was once part of a giant: Colossus, the first programmable, electronic, digital computer. In the early 1940s, British engineer Tommy Flowers designed Colossus to crack the cipher of that fishy machine, the "Tunny." Thanks to me and Tommy, the Allies read German war plans in almost real time. But you’ve probably never even heard of us, right? That’s because, after the war ended, the British kept us secret for thirty years. People even left us out of the computer history book. Now the secret’s out!

Stepping switch from Colossus Mark II computer, UK, 1944