A disc jockey, (usually called by the initialism "DJ", or "deejay"), is an individual who selects and plays pre-recorded music for the enjoyment of others.
DJs can be heard on the radio or at any number of social gatherings, among them weddings, nightclubs, art openings, warehouse parties[?], or high school dances. As a result there are many different types of DJ, each fitting into a particular niche defined by performance setting (broadcast booth or nightclub) and intended audience (jazz or hip hop fans). A DJ's performance style and the techniques they employ reflect these considerations. Wedding DJs play music but are often expected to act as a masters of ceremonies who introduce the bride and groom, lead dances, or invite guests to play games. A DJ at a rave would not be expected to do any of these things, but would be expected to introduce a greater technical element to their performance by manipulating the songs they play in order to maintain a given tempo and energy level. It can be said that DJing isn't a single action but instead a series of actions whose makeup is predicated upon a number of situational factors and expectations. The examples of talk radio "shock jocks[?]" like Howard Stern and Don Imus[?] show that one need not play music to be considered a DJ by some audiences, though the title "on-air personality[?]" might be more appropriate for them.
