Computer media players use specific playlist formats to organize compatible music and media files in the player. Two common file types are the M3U (MP3 Playlist) and WPL (Windows Playlist) extensions. The differences between an M3U and a WPL file lies in their identifying characteristics and primary associations. The primary association of a playlist extension indicates the type of player that uses the file type.
WPL is used by the Microsoft Windows Media to create playlists of audio compatible with that software. M3U is associated with the MP3 audio format, which is used by a wide variety of software and audio player developers.
The M3U extension has MIME (Multipurpose Internet Mail Extensions)capabilities, while the WPL format does not. MIME is a global formatting standard that allows for a variety of file types to be exchanged over different email servers. For M3U files, this allows the file to instruct the player being used to go to a specific URL on the Internet to locate and play the media file. WPL files do not have this capability and must be downloaded to the Windows Media Player to be used.
The hexadecimal identifiers used to describe each playlist extension allow computers to translate the format into a binary language (0 and 1) that forms all machine language and is what allows computer software to function. Since each binary descriptor consists of 8 positions, using a hexadecimal system shortens the code needed to identify the format. The Hex Identifier for an M3U is 23 45 58 54 4D 33 55 0D 0A. The Hex identifier for a WPL format is 4D 69 63 72 6F 73 6F 66 74 20 57 69 6E 64 6F 77 73 20 4D 65 64 69 61 20 50 6C 61 79 65 72 20 2D 2D 20.
Both types of files can be edited using text editors, as they are lists of media file locations and not the media file itself. When edited, the file must be saved with an ASCII identifier along with the extension WPL or M3U. This identifier is used by software in a manner similar to the hexadecimal identifier to read the file. The ASCII identifier for an M3U file is #EXTM3U and for the WPL file it is Microsoft.Windows.Media.Player.--.