Flag alphabet

flag used to communicate something about the ship flying it from a distance

Ships use the flag alphabet to exchange messages. They do this optically, using signal flags. There are different ways in which this can be done:

  • Each flag can represent a letter, all the flags spell out the message
  • A flag used alone usually has a special meaning. A boat supporting a diver will show the "A flag"
  • Several flags used together can form a code, which can be looked up in a code book both ships have.
  • In ship races, flags have different meanings:
Two ships with signalling flags
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