.M3U files is a common standard used in creating MP3 Playlists’. An M3U file is basically a plain text file that stores the location of different media that the mediaplayer should play. It is not the media file itself but rather a pin-pointing mechanism for them.
An M3U file simply tells the player where the real song track is located and in what order is the song list to be played. Originally, Winamp was the first player to support this format, but slowly with time, M3U has become the de facto format for media playlists. Mostly all desktop media players now support M3U playlists, and you can play and create playlists from within the application.
If you have an M3U file on your computer, you should be able to play it with any music player installed on your system. On Windows, just right click the file > Select Open As’ > Select the player you wish to play it with.
As made obvious, M3U files can’t be burnt to CDs and other devices as such because they just point to the original media. When transferring you songs from your computer to another device, make sure you transfer the real files instead of M3U playlists.