Gatefold

It became famous as an extension of progressive rock, as the expansive, transient gatefolds by artists such as Roger Dean, H. R. Giger, or Hipgnosis became associated with concept albums.

While some multi-LP releases (particularly those issued during the vinyl record's market dormancy from 1988 to 2007) would either package the discs in a simple sleeve or sandwich the records between two cards and shrink wrap, the prominence of gatefold for multi-LP albums led it to become the most common form of packaging for them.

Starting in the early 1950s, RCA used gatefold packaging for some of their deluxe 45 RPM single releases, such as Nat King Cole's eight-song "Unforgettable" EP, with two 45s, released in 1952.

Gatefold packaging for LPs was popularized in the late 1950s by band leader and stereophonic studio recording pioneer Enoch Light so he could fit liner notes he had written describing the sounds in each song on the album sleeve.

[1] The LP gatefold has also been adapted to package CDs without a jewel case.

Gatefold issue of rock band Queen 's Made in Heaven CD
An example of an LP gatefold from a vinyl copy of the Beatles' 1968 self-titled release . (The four portraits of the band members on the right have been blurred out for copyright reasons.)
The left and right panel of a gate-folded sheet open like a double gate.