.ITL File Extension

Database used by iTunes to organize files in the iTunes music library; contains a list of songs in the library, playlists created by the user, song ratings, and comments.

In Windows, the iTunes library file is saved in the following location:
\Documents and Settings\username\My Documents\My Music\iTunes\iTunes Library.itl

On the Mac, the iTunes library file is saved in:
/Users/username/Music/iTunes/iTunes Library

Notice that the Mac version of the iTunes library file does not include the ".itl" file extension. However, both the Mac and Windows versions of iTunes save a related file called "iTunes Music Library.xml" in the same directory. This file makes the music and playlists available to other applications (such as iPhoto and iMovie on the Mac).

If the iTunes library file is deleted, iTunes can recreate it by searching for songs in the Music folder. However, all playlists, song ratings, and comments will be lost.