About
As music storage and playback using personal computers became common, the term playlist was adopted by various media player software programs intended to organize and control music on a PC. Such playlists may be defined, stored, and selected to run either in sequence or, if a random playlist function is selected, in a random order. Playlists' uses include allowing a particular desired musical atmosphere to be created and maintained without constant user interaction, or to allow a variety of different styles of music be played, again without maintenance.

Several computer playlist formats for multimedia players, such as PLS, can pass a playlist or URL to the player. In the case of radio stations it can also link many audio players directly to the station's live streaming audio, bypassing any need for a web browser. (In that case the playlist file is typically downloaded from the station's live streaming web page, if offered. The files are similar to Internet shortcut files in appearance and internal structure, except used by media players rather than web browsers.)

Some Internet streaming services, such as Spotify, Amazon Music, 8tracks, and the defunct Playlist.com and Webjay, allow users to categorize, edit, and listen to playlists online. Other sites focus on playlist creation aided by personalized song recommendations, ratings, and reviews. On certain sites, users create and share annotated playlists, giving visitors the option to read contextual information or reviewer comments about each song while listening. Some sites only allow the sharing of the playlist data with the actual music being delivered by other channels, e.g., Plurn, others provide a closed catalog of content from which the playlists can be generated while sites like imeem allow users to upload the music to central servers to be shared and accessed by any user of the site. iPods can also be used to build playlists.

Most media players, such as Winamp, can easily create custom playlists from one's media library. For example, in a software MP3 player for Windows, Android, or macOS, the desired tunes are typically dragged and dropped from the user's music library into the player's "edit or create playlist" window and saved.

The idea of automatically generating music playlists from annotated databases was pioneered by François Pachet and Pierre Roy.[7] Constraint satisfaction techniques were developed to create playlists that satisfy arbitrary "sequence constraints", such as continuity, diversity, similarity, etc. Since, many other techniques were proposed, such as case-based reasoning