iTunes uses a number of library files to store metadata and manage your media. By default, they are store in the iTunes folder inside your Music folder. (If you’re on a Mac, this is in your home folder; that’s the one with the house icon and your user name. If you use Windows, it’s in \My Music\iTunes, in your user folder.)
Here are the files you may see:
- Album Artwork stores a cache of artwork that is embedded in your files, and stores downloaded artwork for purchased tracks, or for Apple Music tracks.
- iTunes Library Extras.itdb contains some data downloaded from the Gracenote CD Database.
- iTunes Library Genius.itdb stores information about your library for use by Genius, if you have activated Genius. If you use iCloud Music Library, then Genius is on, and you cannot turn it off.
- iTunes Library.itl is the main iTunes library file. It stores information about all your media files, including metadata. This is the file that iTunes reads when you display content in iTunes, when you search, when you create smart playlists, etc. This is the most important file for your iTunes library.
- iTunes Library.xml is a file that iTunes writes from the iTunes Library.itl file. This is only used for third-part apps to be able to read what’s in your library. And, by default, this file is no longer written. iTunes only writes this file if you check Share iTunes Library XML with other applications in the Advanced preferences. I recommend doing so, because if you ever have a corrupted library, you may be able to rebuild your iTunes library from this file. It’s good to have backups of this file too.
- iTunes Media is the folder that contains your iTunes media files. You may store it in a different location, such as on an external disk or network volume.