VLC media player is an open source video and audio player capable of playing almost any type of media including DVDs and VCDs. In addition to being able to play most video and audio files, VLC can also post free ads without registration
File extensions that can be opened by vlc-media-player

xo.ASX	Advanced Stream Redirector
xo.DTS	Digital Theater Systems Audio File
xo.GXF	General eXchange Format
xo.M2V	MPEG-2 Video
xo.M3U	MP3 Uniform Resource Locator
xo.M4V	MPEG-4 Video File
xo.MPEG1	MPEG-1 Video
xo.MPEG2	MPEG-2 Video
xo.MTS	AVCHD Video File
xo.MXF	Material eXchange Format
xo.OGM	Ogg Multimedia Container File
xo.PLS	Playlist
xo.BUP	DVD Information File
xo.A52	Dolby Digital AC-3 Compressed Audio File
xo.AAC	Advanced Audio Coding Compressed Audio File
xo.B4S	Winamp 3+ Playlist
xo.CUE	Cue Sheet
xo.DIVX	DivX Movie
xo.DV	Digital Video
xo.FLV	Flash Video
xo.M1V	MPEG-1 Video
xo.M2TS	MPEG-2 Transport Stream Videos
xo.MKV	Matroska Video Stream
xo.MOV	Apple QuickTime Movie
xo.MPEG4	MPEG-4 Video
xo.OMA	OpenMG Audio File
xo.SPX	Ogg Speex Audio File
xo.TS	DVD Video
xo.VLC	VLC Media Player Data
xo.VOB	DVD Video Object
xo.XSPF	XML Shareable Playlist Format
xo.DAT	VCD Video
xo.BIN	Binary DVD Video
xo.IFO	DVD Information File
xo.PART	Partially Downloaded File
xo.3G2	3G Mobile Phone Video
xo.AVI	Audio Video Interleave
xo.MPEG	MPEG Video
xo.MPG	MPEG Video
xo.FLAC	Free Lossless Audio Codec Compressed Audio FIle
xo.M4A	MPEG-4 Audio File
xo.MP1	MPEG-1 Audio Layer I
xo.OGG	Ogg Multimedia Container File
xo.WAV	Waveform Audio
xo.XM	Extended Module Audio File
xo.3GP	3G Mobile Phone Video
xo.SRT	DVD Subtitles File
xo.WMV	Windows Media Video
xo.AC3	Dolby Digital AC-3 Compressed Audio File
xo.ASF	Advanced Systems Format Video
xo.MOD	MOD Audio File
xo.MP2	MPEG-1 Audio Layer II
xo.MP3	MPEG-1 Audio Layer 3
xo.MP4	MPEG-4 Part 14 Multimedia Container
xo.WMA	Windows Media Audio File
xo.MKA	Matroska Audio Stream
xo.M4P	Protected AAC File

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