How Does an Enigma Machine Work?

This is a completely fantastic look at how the Enigma Machine works. Jared Owen constructed a 3D model of the German cipher device and clearly walks the viewer through how the electricity flows through the machine to scramble and unscramble secret messages.

When electricity travels through one rotor it changes the letter once. But remember, we have three of these rotors and they each have different wirings on the inside. When electricity travels through all three of them it changes the letter three times.

Then at the end, we have the reflector. This also has 26 metal contacts. Inside is more wiring that connects the letters in pairs. So it goes in as one letter and then comes out as another letter.

To the right of here is the input wheel. It has 26 wires that go in and connects to the 26 metal contacts.

Let’s put this all together. Electricity flows through one of the 26 wires, let’s say the wire for the letter Y. Then it gets changed to a different letter at all three rotors. Then it hits the reflector, which again, changes the letter. And then it goes back through the rotors again which changes the letter three more times. And it comes back out on a wire that represents a completely different letter. And if you were counting, this means the letter was changed seven times.

Seriously, this is one of the best explanations I’ve ever seen of anything on YouTube — by the end of it, I was pretty sure I could now build an Enigma Machine if I needed to. (via benn jordan)

• Enigma machine
• Jared Owen
• video