Semaphore was invented by Rev Lord George Murray on 1 January 1796. Semaphore is the telegraphy system conveying information at a distance by using visual signals with hand held flags, rods, disks, paddles and occasionally bare or gloved hands. Semaphores were adopted and widely used in the maritime world in the 19th century.
The current flag semaphore system uses two short poles with square flags, which the signalman holds in different positions to signal letters of the alphabet and numbers. Except for in the rest position, the flags never cross over. Flags for used at sea are yellow and red (the Oscar flag) while flags used on land are blue and white (the papa flag).