Bootleg – A recording that has been manufactured and distributed illegally by individuals or companies without the authorisation of the artist(s) or the royalty holder(s).

Catalogue Number – (cat No #) A number assigned to a release by the record company. Generally different formats of the same release will each have their own catalogue number.

Digipack - Packaging that consist of a gatefold paperboard or card stock outer binding.

Enhanced CD – (CD Extra, CD Plus) Multisession discs that contain music and additional multimedia data such as text, graphics, audio, video, animation, and computer data.

Jewelcase - Standard plastic case that has been used since the compact disc was first released in 1982

Matrix - The Matrix code is the letters and numbers printed on a compact disc in the mirror band close to the center of the CD. Being aware of the correct Matrix code of a rare CD will help you identify whether the item is genuine or bootleg.

Mint – The top condition of the music grading system. When a used CD is referred as ‘Mint’ then the disc, the cover and all the inserts should be in absolutely perfect condition.

Obi - A small slip of paper with the title and song lists printed in Japanese, inserted between the shrink-wrap and the jewel case of Japanese CD releases.

OOP – (Out Of Print) An album is considered as OOP when it is not available any more from the record label and from its distributors. An OOP CD is not necessarily sold out as there might be copies still available in the shops and elsewhere.

Promo – (Promotional/sample/freebie) Promotional CDs that are given by the record label to the media and to the music industry in advance of the release date.

Re-release – (reissue, re-edition) An album which has been released at least once before and is released again with or without alterations or additions.

Scuffs – Physical marks on the playable size of a CD. Scuffs can be caused due to inappropriate use/storage of the disc or by environmental exposure. A small amount of scuffs will not affect play.