Semaphore

Semaphore is a way to send messages using flags. A person holds a flag in each hand and moves their arms to different positions. Each position stands for a different letter or number. Semaphore was invented before telephones and radios, when people needed to communicate over long distances.

How Semaphore Works

The sender holds two flags, one in each hand. By moving their arms to different angles, they signal different letters of the alphabet. The receiver watches from a distance and reads the message letter by letter. On ships, semaphore flags are usually red and yellow.

Semaphore in History

Semaphore was widely used by navies around the world. Ships at sea used flag semaphore to communicate with each other and with the shore. The French built a system of semaphore towers in the 1790s that could relay messages across the country. Today, semaphore is mostly used by scouts and for fun.

Fun Facts

• The French semaphore system could send a message from Paris to the coast in just minutes.
• Boy Scouts and Girl Scouts sometimes learn semaphore as part of their signaling badge.
• The peace symbol was designed using semaphore letters N and D, standing for nuclear disarmament.

Did You Know?

The famous peace symbol from the 1960s was created by combining the semaphore signals for the letters N and D.