The measure of a code's greatness lies in the way it mixes things up.
Letters and numbers, dots and dashes, symbols and spaces - it's the collision of media that creates a smokescreen through which the unenlightened can't see. That's why the key to a Position Cipher is, well, a key. When paired with a secret communiqué, the key indicates which letters to pull out and line up to spell the real message. For instance, look at the notched belt below and take note of the letters it's calling out:
Pay attention to the notched letters and you get the hidden message "I need a new belt" — how true!