CD booklets

Liner notes (also sleeve notes or album notes) are the writings found on the sleeves of LP record albums and in booklets which come inserted into the Compact Disc jewel case or the equivalent packaging for vinyl records and cassettes.

Liner notes are descended from the notes of text that were printed on the inner sleeve used to protect a traditional 12-inch vinyl record, i.e., long playing or gramophone record album. The term descends from the name "record liner" or "album liner". On vinyl recordings, the most common placement of these notes would be the paper sleeve inside an album jacket that served to protect the record from dust (dust sleeve or dust liner, etc.). As the rear covering of an album jacket was applied in early days in a fashion that resembled the tailored lining of garments (overlapping and protecting the edges of the front cover), it's also likely that "liner" could have been a printer's terminology for this back cover area as well. From the early days of recording to the present time, album liner notes have evolved in all musical genres and across different formats from vinyl LP to cassette to CD, with varied styles of writing employed by artists and record makers to either complement or supplement the music.

Such notes often contained a mix of factual and anecdotal material, and occasionally a discography for the artist or the issuing record label. Liner notes were also an occasion for thoughtful signed essays on the artist by another party, often a sympathetic music journalist, a custom that has largely died out. However, the liner note essay has survived in retrospective compilations, particularly in box sets. It is also a tradition in Japan especially for foreign artist releases in Japan. Many CD liner notes include complete song lyrics for the album.

Liner notes now usually include information about the musician, lyrics, a personnel list, and other credits to people the musicians want to thank and people or companies involved in the production of the music. They also can give details on the extent of each musical piece, and sometimes place them in historical or social context. Liner notes for classical music recordings often provide information in several languages; if the piece includes vocal parts, they will often include a libretto, possibly also translated into several languages.

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