Media Management
iTunes keeps track of songs by creating a virtual library, allowing users to access and edit a song's attributes. These attributes, known as metadata, are stored in two separate library files. The first is a binary file called iTunes Library and it uses a proprietary file format ("ITL"). It caches information like artist and genre from the audio format's tag capabilities (the ID3 tag, for example) and stores iTunes-specific information like play count and rating. iTunes typically reads library data only from this file. The second file, iTunes Music Library.xml, is refreshed whenever information in iTunes is changed. It uses an XML format, allowing developers to easily write applications that can access the library information (including play count, last played date, and rating, which are not standard fields in the ID3v2.3 format). Apple's own iDVD, iMovie, and iPhoto applications all access the library. If the first file exists but is corrupted, such as by making it zero-length, iTunes will attempt to reconstruct it from the XML file. Detailed third-party instructions regarding this are documented elsewhere. Beginning with iTunes 10.5.3 this behavior has been changed such that the XML file is not read automatically to recreate the database when the database is corrupted. Rather, the user should load the iTunes Library.xml file via File > Library > Import Playlist....
It has also been noted that iTunes does not automatically track changes to actual files in the library. If a file is moved or deleted, iTunes will display an exclamation mark beside the library entry and the user will need to manually amend the library record. Several third party tools address this problem.
iTunes supports ripping from CDs, but not from DVDs. However, in 2008, Apple and select film studios introduced "iTunes Digital Copy", a bonus feature on some DVDs that provides a copy-protected and iTunes-compatible file for select films.
Famous quotes containing the words media and/or management:
“The media transforms the great silence of things into its opposite. Formerly constituting a secret, the real now talks constantly. News reports, information, statistics, and surveys are everywhere.”
—Michel de Certeau (1925–1986)
“The care of a house, the conduct of a home, the management of children, the instruction and government of servants, are as deserving of scientific treatment and scientific professors and lectureships as are the care of farms, the management of manure and crops, and the raising and care of stock.”
—Catherine E. Beecher (1800–1878)