Last year, I linked this story from The Atlantic that explored the mechanics of a dial-up modem connection, elegantly described as "20th century technology tunneling through a 19th century network." Alexis Madrigal, the writer of that piece, just shared this awesome image breaking down a modem handshake with even more depth. (click it to enlarge.) It's even color-coded to let you know whether a sound is made by the dialing or receiving end. Machine linguistics! (h/t @alexismadrigal)