Metadata is used to name, describe, catalog and indicate ownership or copyright for a digital audio file, and its presence makes it much easier to locate a specific audio file within a group - by using a search engine that reads the metadata. As different digital audio formats were developed, it was agreed that a standardized and specific location would be set aside within the digital files where this information could be stored.
As a result, almost all digital audio formats, including mp3, broadcast wav and AIFF files, have similar standardized locations that can be populated with metadata. This "information about information" has become one of the great advantages of working with digital audio files - since the catalog and descriptive information that makes up the metadata is built right into the audio file itself, ready for easy access and use. You no longer need to consult a paper catalog or product packaging to find out more about a particular file.