Digipak is a style of optical disc packaging, a registered trademark of AGI-Shorewood, an Atlas Holdings LLC company.
Digipak often consist of a gatefold (a gatefold is a type of fold used for advertising around a magazine or section, and for packaging of media such as the phonographic industry) paper or card stock outer binding, with one or more plastic tray to put a CD/DVD into.
Since digipak is like a jewel case to major record company, it is often used generically. Digipak-style packaging often used for CD singles or special album release. It's also used as a premium package for DVDs or DVD sets such as the concert of the artist. Some of the packaging that are made out of paper mostly wear out faster than plastic (unless you drop it or step on it). Digipak and CD can also be damage by UV ray so licensed digipak manufacturers such as domestic U.S. printer and disc replicator Oasis Disc Manufacturing recommend coating the raw printed paper with a protective UV coating (the substance in you sunscreen), thus ensuring greater longevity. 
The tray of the CD must be the strongest out of the whole digipak, it should remain brittle and prone to cracking if the package is crushed. Digipak peak it top point in the early 2000s.
Nowadays manufacture try to find a way to reduce the coat of the digipak and have sough to reduce environmental impact and improve functionality y using recyclable material being PET tray from recycled bottle. They also replace the "teeth" (tray) with egg cartons. Many printers use recycled or sustained material for the board stock. There are many different styles of digipaks which have different templates as seen on the left, the numbers of panels varies for each digipak design.