ASX files: The ASX file type is associated with 'Advanced Stream Redirector File' by Microsoft Corporation. It is primarily a playlist shortcut which gives the media player, the information on how to present the media file that is contained within the play list. It is basically a multimedia playlist or shortcut to an audio/video file (often an .ASF file); references one or more URLs that point to the locations of the audio and video files; used for storing multimedia playlists.