The History behind the Second Day’s Code: The International Maritime Code

6a00d83453e6e169e20120a695ff47970b-320piThe Commercial Code of Signals (later called the International Code of Signals) launched in 1857 consisted of 18 flags. Unlike the secret naval codes, this maritime code was designed to be memorized and did not require a detailed code book to be understood. Each flag represents a letter or number (note that only letters are depicted in the video), but the letter flags, when raised individually, have specific meanings — usually a warning. Ships still use a modified version of this code today. For example, a three-letter flag combination identifies a ship’s nationality. — Excerpted from The Book of Codes, page 93.

Check out the second video.

Tips and Tricks for the Crack the Code Sweepstakes

While reviewing each day’s video, the pause/play button and forward/backward controls are your friends. Use them often and to great effect.

For those new to Twitter, here’s a great explanation of how to direct message.

If you miss your chance to send your solution to the day’s code, you’ll have more chances to win as the week progresses, with a big chance to win $100 in UC Press books at the end of the week in our Grand Prize Drawing. You can always find the rules for the Sweepstakes here.