APE tag
An APE tag is a tag used to add metadata, such as the title, artist, or track number, to digital audio files.
Versions
APEv1
The APEv1 tag was designed for the Monkey's Audio format. In MP3 files, the APE tag is stored at the very end of the file, with no inline declaration in the body of the file. The software handles the writing and access to the tag and does not interfere with the contents of the MP3.
APEv2
The Musepack format developer, Frank Klemm, extended the original APE tag format to add a header, allowing APE tags to be at the beginning of files and allowing metadata values to be Unicode rather than simply ASCII. Because of its simplicity and flexibility, APEv2 was adopted by the WavPack and OptimFROG formats as their primary tag format. Version 3.99 of the official Monkey's Audio software switched from using APEv1 to APEv2.
The popular media player software, Winamp, supports reading and writing of APEv2 tags in MP3 files. foobar2000 and Jack! The Knife can tag MP3 files with APEv2 tags instead of ID3 tags. Some music library managers and mass taggers such as MusicBee or Mp3tag also support this feature. The tagging string APETAGEX signals the start of an APEv2 record, and the string TAG signals the start of an ID3v1 tag.
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