Booing is the act of showing ispleasure for someone or something, generally an entertainer, by loudly yelling "Boo" (and holding the "oo" sound) or making other noises of disparagement, such as animal noises. The sounds of donkeys, snakes, geese, cattle and cats are quite popular. The sound is often accompanied by one or two hands giving the thumbs down sign. If spectators particularly dislike the performance they may also accompany booing by throwing objects onstage, though the objects may not be meant to physically hurt the performer. Booing can also be expressed to startle someone.