Learn semaphore with Crackers the crab

If you get shipwrecked on a desert island you might need to send a message asking for help to passing ships. You could do this using semaphore signals.

Semaphore is a way of sending messages over long distances, using two hand-held flags. The person sending the message holds the flags in a different position for each letter of the alphabet.

Type a short message into the box below and Crackers will show you how to signal it with semaphore.

You can also have a go at sending semaphore messages yourself using our semaphore A-Z|.

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