Some Wikipedia articles include sound or video files, that 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 or MP3 audio format, and video files use the VP9 or Theora format, both contained in either WebM or Ogg files. However, Microsoft Windows, iOS, and older macOS do not support these formats by default, and depend on software to play the files. When you use Wikipedia in a browser this software is integrated by default.
Music files may occasionally use the MIDI format (.MID or .MIDI extension). Wikipedia can play a MIDI file by converting it to digital audio, or depending on how the MIDI file is linked it may rely on your computer's browser and hardware to play the MIDI file.
For help making and converting video and audio into the format usable on Wikipedia, see Wikipedia:Creation and usage of media files.