A disc jockey (often referred to as a DJ or deejay) is the person who selects and plays previously recorded music for an audience.
DJ tools are music-oriented software utilities that will allow disc jockeys to easily create their playlists and to configure the order the tracks will be played.
These applications will also allow DJs to apply effects onto the songs, thus creating original mixes and song transitions.
There are also some software solutions that will allow DJs to start karaoke sessions without requiring any additional hardware or software.