[[Image:MediaHelp.jpg|frame|right|Some Wikipedia articles contain sound and video files]]
Some Wikipedia articles include '''sound''' or '''video''' files, which can be played on almost all personal computers. However, your computer must have the right software. If your computer does not automatically play these files when you click on them, downloading and installing free software from the internet can enable it to do so.
Sound files on Wikipedia generally use the [[Vorbis]] audio format, and video files use the [[Theora]] format, both contained in an [[Ogg]] file. These are analogous to other formats used to play digital audio and video such as [[MP3]] and [[MPEG]]. The difference is that [[Ogg]] formats are completely free and open for further software development. However, [[Microsoft Windows]] and [[Mac OS X]] do not support these formats by default, and require additional software to play them (see below).
Music files may occasionally use the [[Musical Instrument Digital Interface#MIDI file formats|MIDI]] format (.MID or .MIDI extension). MIDI is generally playable without additional software, as most computers have a MIDI-enabled player and sound card.