ID3
ID3 is one of the oldest ways of storing Metadata. ID3 is intended to be used with mp3 files only. There are two major versions.
ID3v1
This is a very basic tagging format. It's limited to the following fields:
- Song title
- Artist
- Album
- Year
- Comment
- Genre
- Album track (ID3v1.1)
ID3v2
ID3v2 is much more advanced than version 1, all fields can be defined freely. It also supports embeding pictures and other data. A rewrite of the file is necassary each time you update an ID3v2 field.