Classic crypto fun

It turns out that there's a much better way to kill a few minutes than looking at movies of cats playing with their favorite toys on YouTube. Instead, you can try a simulator of the classic Enigma machines, the devices that the Germans used to encrypt diplomatic and military communications in World War 2. The picture above may be a bit hard to see, but it shows that if you use the key "LWM" to encrypt the message "HELLOWORLD" with a three-rotor Enigma, you get the ciphertext "KSWKUXBXOV." This simulator also shows how the Enigma works. At each step, it shows you the path through the machine that creates each letter of ciphertext and how the rotors move to change the setup that the machine will use to create the next letter of the ciphertext. If you're even more interested, you can also find a paper that describes how to break the Enigma's encryption here.