A: There are several video formats available. Some are generic and can be played by many programs, while some are proprietary formats than can only be played using a specific program. Below is a list of programs that should help you find the player you need.

Windows:

Company	Program Name	Primary Formats	Notes
ALTools	ALShow	n/a	Includes several codecs for playing different video formats; supports captions and subtitles; can capture images, video, and audio clips.
Apple	QuickTime Player	.MOV, .QT	Multimedia player developed by Apple; plays QuickTime movies and many other formats; supports H.264 and various other codecs.
CyberLink	PowerDVD	n/a	Popular video playback program that supports MPEG-2 HD, MPEG-4 AVC, WMV-HD, DVD-Video, Mini-DVD, and DivX Pro formats.
DivX	DivX Player	.DIVX	Plays videos encoded with the DivX codec, a high-quality, high-compression video format; supports 1920x1080 HD video and other resolutions.
Gabest	Media Player Classic	n/a	Compact free media player with an interface similar to Windows Media Player 6; based on the DirectShow architecture and supports a wide range of video formats; also known as "MPC."
Microsoft	Windows Media Player	.WMA, .WMV, .ASF	Audio and video player developed by Microsoft; bundled with the Windows operating system; plays Windows Media files and several other formats, including AVI files.
MPlayer Project	MPlayer	n/a	Open source media player; supports a large number of formats; can save streaming media to a file.
Participatory Culture Foundation	Miro	n/a	Miro is a free open-source audio and video player designed for fullscreen HD video playback; it supports several different file formats and can play television shows from online sources.
RAD Game Tools	The RAD Video Tools	.BIK	Supports the Bink Video Codec, commonly used by video games; The RAD Video Tools includes both the Bink and Smacker compressors.
RealNetworks	Real Player	.RA, .RM, .RAM	Plays local and streaming Real Media audio and video files; also supports other basic video formats.
VideoLAN	VLC Media Player	n/a	Compact cross-platform media player; supports several formats including MPEG-1, MPEG-2, MPEG-4, and DivX; can also play DVDs, VCDs, and streaming multimedia files.

Macintosh:

Company	Program Name	Primary Formats	Notes
Apple	QuickTime Player	.MOV, .QT	Multimedia player developed by Apple; bundled with the Mac OS X operating system; plays QuickTime movies and many other formats; supports H.264 and various other codecs.
DivX	DivX Player	.DIVX	Plays videos encoded with the DivX codec, a high-quality, high-compression video format; supports 1920x1080 HD video and other resolutions.
Microsoft	Windows Media Player	.WMA, .WMV, .ASF	Audio and video player developed by Microsoft; plays Windows Media files and several other formats, including AVI files.
MPlayer Project	MPlayer	n/a	Open source media player; supports a large number of formats; can save streaming media to a file.
Participatory Culture Foundation	Miro	n/a	Miro is a free open-source audio and video player designed for fullscreen HD video playback; it supports several different file formats and can play television shows from online sources.
RAD Game Tools	The Bink Video Player	.BIK	Plays Bink files, which are typically used in video games; available in both PowerPC and Intel versions.
RealNetworks	Real Player	.RA, .RM, .RAM	Plays local and streaming Real Media audio and video files; also supports other basic video formats.
VideoLAN	VLC Media Player	n/a	Compact cross-platform media player; supports several formats including MPEG-1, MPEG-2, MPEG-4, and DivX; can also play DVDs, VCDs, and streaming multimedia files.

Linux:

Company	Program Name	Primary Formats	Notes
Kaffeine	Kaffeine - KDE Media Player	n/a	Media player for the K Desktop Environment (KDE); supports DVD and VCD playback as well as Digital TV streams; also plays multiple audio formats.
MPlayer Project	MPlayer	n/a	Open source media player that supports a large number of video formats; can save streaming media to a file.
Participatory Culture Foundation	Miro	n/a	Miro is a free open-source audio and video player designed for fullscreen HD video playback; it supports several different file formats and can play television shows from online sources.
RAD Game Tools	Bink Video command line Player	.BIK	Plays Bink video files, which are commonly used in video games; can also play compiled Bink EXE files.
RealNetworks	Real Player	.RA, .RM, .RAM	Plays local and streaming Real Media audio and video files; also supports several other standard video formats.
VideoLAN	VLC Media Player	n/a	Compact multiplatform media player that supports dozens of different audio and video formats; can also play DVDs and VCDs.

Know of another video player that should be listed here? Suggest an addition.