What Is Music Tagging?

What is song metadata and why is it hidden in your digital music files?

Man listening to music on iPad
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Music metadata, which is also referred to as ID3 metadata, is the information embedded in an audio file that is used to identify the content. This data which is in most (if not all) of the files in your digital music library, can be used by a wide range of consumer electronic devices and software programs. The most common reason for using embedded metadata in a digital audio file is for identification purposes. The details of a song, for example, can be displayed during playback to make it easy for you to identify it.

About Metadata

Depending on the audio format used, a special area—normally at the start or end of the file—is reserved for metadata that identifies the encoded audio in several ways. This information can be useful for managing and organizing your library. Examples of the types of information that can be stored in an audio file's metadata area include:

  • Song title
  • Band or artist's name
  • Album name that the song originates from
  • Type of music (genre)
  • Album track number
  • Year the song was released

For the MP3 format, the two common metadata systems that are used for tagging audio files are called ID3v1 and ID3v2—this is where the term ID3 tags comes from. The first version of ID3 (v1), stores the metadata information at the end of an MP3 file with allocated space for up to 128 bytes of data. In version 2 (ID3v2), the metadata is located at the start of an MP3 file and is a frame-based container format. It is far more capable and has a much larger capacity for storing metadata—up to 256 Mb.

How to View or Edit Music Tags

Music metadata can be edited and viewed using various types of software:

The Benefits of Using Music Metadata on Hardware Devices

The advantage of using music metadata on hardware devices such as MP3 players and CD players is that the song information can be directly displayed on-screen (if there is one). You can also use metadata to organize your music library and create playlists directly on the hardware device. For example, on most modern MP3 players, it is easy to select only the songs by a particular artist or band to be played by using the artist metadata tag as a filter. You can quickly cherry-pick songs using this method in other ways too for fine-tuning your music selections.