Likewise, string musicians of an orchestra use the bobbing their bows in the air or gently tapping them on their instruments' strings as a substitute for applause. Wind section members will generally lightly stamp their feet or pat one hand on their leg to show approval to a conductor or soloist, while percussionists often rap drumsticks together. An even more subtle form of approval may be exhibited by a member of an orchestra during a formal rehearsal or performance when a colleague performs particularly well, usually a slight shuffle of the foot on the floor or hand on the knee. These subtle forms of applause may not be recognized as such by the audience. Outright applause by performers for other performers, although increasingly common, is traditionally regarded as gauche, self-congratulatory, and usurping of the audience's prerogative (and sole task in this respect) to provide accolades when they feel that the performance merits it.