A tagging standard.

Tagging is storing information about an audio file within itself to determine its origin and contents. This makes the file self-documenting. If you transfer it to another computer, MP3 player, etc., the software on this other device read the tags and display the content in the interface.

There are many tagging standards but ID3 is a very popular one simply because MP3 is a popular audio format.


While there are legacy and future standards for ID3 tags, the most popular version implemented today is ID3 version 2.3.