Body Language in USA

Applause is primarily the expression of approval by the act of clapping, or striking the palms of the hands together, in order to create noise. Audiences are usually expected to applaud after a performance, such as a musical concert, speech, or play. In most western countries, audience members clap their hands at random to produce a constant noise; however, it tends to synchronize naturally to a weak degree. As a form of mass nonverbal communication, it is a simple indicator of the average relative opinion of the entire group; the louder and longer the noise, the stronger the sign of approval.

In some Latino and Hispanic cultures , and also in many other European countries, a synchronized, slow handclap at the end of a musical performance signals the audience's desire for an encore.
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