(1) Software that makes audio and video files in the computer available on the network. For discovering files, media server software typically uses the Bonjour or UPnP protocols. For sharing files and playlists, they use DAAP or Windows Media Connect protocols. For example, iTunes uses Bonjour to discover and DAAP to share, while Windows Media Player uses UPnP and Windows Media Connect. See DAAP, UPnP, Bonjour, Windows Media Connect, Firefly, digital media hub and digital media server.

(2) Hardware that stores digital music, images and videos for a stereo or home theater. See digital media server and Media Center Edition.

(3) A computer system in a network that stores multimedia files for downloading over the Internet.

(4) A computer system in an IP telephony network that transmits dial tones, busy signals and announcements such as "the number you have called is no longer in service." The media server can be a separate unit or part of a softswitch (media gateway controller). See IP telephony.