Gatefold album covers are those which open up like a book and reveal some (usually) interesting visuals and text that can not be seen when the vinyl and cover are still sealed in the store-bought shrink wrap. The majority of multi-disc vinyl albums used this type of jacket/cover. Gatefold cover LPs are also perfect examples of the wealth of visuals (photos and artwork) and information (liner notes, bios, song lyrics, etc) which unfortunately almost disappeared with the advent of CDs in the 80’s and the other forms of digital media that followed.