Audiences applaud or clap at the conclusion of a performance to express praise. Although applause has become conventional at the end of all performances, particularly loud or sustained clapping is considered to be high praise. The history of the use of sound to express appreciation goes back for centuries, with different cultures having prevailing traditions around applause.
The root word for “applause” is applaudere, a Latin word meaning to strike or clap. During Roman times, a mild expression of pleasure might be limited to snapping the fingers or patting the hand. An enthusiastic response to a performance would involve full blown clapping, striking the palms of the hands together repeatedly to generate a loud noise. In general, clapping is very rapid and arrhythmic, except in cases where an audience may clap to beat time with a musical performer, as is the case at some folk concerts.
Some rules do govern clapping at performances. By convention, the audience should wait to clap until the performance is concluded. During a theatrical performance, this will be indicated by the curtain call, a procedure in which the actors line up on stage and bow. In a concert or musical performance, the end may not be entirely clear. As a general rule, wait until the house lights start to go up to clap, or until the conductor sets down his baton and bows. An audience should not clap during or between movements or acts, as this may disturb the performers.
Sometimes, an audience will clap in anticipation. Famous conductors are usually applauded as they take the stage, and speakers and politicians are often applauded before they begin. Clapping during a talk also occurs, to express concurrence or praise for an argument or statement. However, sometimes an audience will be asked to refrain from clapping until a speech or debate is concluded, so that the event does not drag on.
A claque, incidentally, is a group of people hired to clap during a performance. Originally, claques were hired by performers who were concerned about a lukewarm reception. In modern performances, a claque is sometimes used to cue the audience, so that they will know when clapping is appropriate. Since many concert audiences are much less cultured than they used to be, the issue of applause breaking out in the middle of a major concert movement is much larger, leading to the need for cues suggesting when clapping is permitted.