an universal player. Ampache doesn't use codecs. It simply streams the music to your player / web browser. If set up properly, it can convert music on the fly in case you use a player that doesn't read a specific format. For instance, if your player doesn't support FLAC, Ampache can Transcode it on the fly to mp3 or any other format.
Few functionalities...
Web Player (HTML5 and/or Flash web players) (embedded or popup)
Subsonic Backend (any subsonic client can play Ampache content transparently)