VLC media player is a highly portable multimedia player for various audio and video formats as well as DVDs, VCDs, and various streaming protocols without external codec or program.

It can also be used as a server to stream in unicast or multicast in IPv4 or IPv6 on a high-bandwidth network.
VLC can play:

MPEG-1, MPEG-2 and MPEG-4 / DivX files from a hard disk, a CD-ROM drive, and so on
DVDs, VCDs, and Audio CDs
From satellite cards (DVB-S)
Several types of network streams: UDP/RTP Unicast, UDP/RTP Multicast, HTTP, RTSP, MMS, etc.
From acquisition or encoding cards (on GNU/Linux and Windows only)