What is "clapperboard"

clapperboard \clap"per*board`\ (kl[a^]p"p[~e]r*b[=o]rd`), n. a device which synchronizes sound and picture while making a motion picture, consisting of boards held in front of a movie camera, which are are banged together.

n. (context film English) A device used in film production, having hinged boards that are brought together with a clap, used to synchronize picture and sound at the start of each take of a motion picture or other video production.

n. photographic equipment used to synchronize sound and motion picture; boards held in front of a movie camera are banged together

A clapperboard is a device used in filmmaking and video production to assist in the synchronizing of picture and sound, and to designate and mark particular scenes and takes recorded during a production. The sharp "clap" noise that the clapperboard makes can be identified easily on the audio track, and the shutting of the clapstick can be identified easily on the separate visual track. The two tracks can then be precisely synchronised by matching the sound and movement. Other names for the clapperboard include clapper, clapboard, slate, slate board, slapperboard, sync slate, time slate, sticks, board, and sound marker.

When a movie's sound and picture are out of synchronization, this is known as lip flap.

Clapperboard is the name of a 1970s children's television programme, hosted by Chris Kelly which covered the cinema. The show was made by Granada Television for the ITV network, and lasted 254 episodes. It was produced by Muriel Young and was broadcast between April 1972 and January 1982. Young herself fronted the show on occasions when Kelly was unavailable.