To be recognized by most players, the file should follow the format. Each entry consists of two lines:
Use relative paths (e.g., song1.mp3 ) if the M3U file is in the same folder as your music. Use absolute paths (e.g., C:\Users\... ) if it is stored elsewhere.
A .m3u file is a plain text playlist format used by media players like VLC, iTunes, and Winamp to queue up music or video streams.