From wikipedia:
A digipak is a compact disc or DVD packaging. It consists of one or more plastic trays contained in a cardboard of various shapes and forms (typically a book cover format). Usually digipak versions of CDs are deluxe versions commonly containing bonus material as opposed to jewel cases that are usually the regular editions. The downside, however, is that digipak editions usually wear off easily as opposed to rather sturdy standard Jewel Case editions. As a consequence, collectors often tend to leave their special edition digipaks in shrinkwrapping and listen to the standard edition or open the digipak once to make a backup of the music CD.
They come in various formats.
eg.
