The jewel case is the standard case used for most CDs. The case consists of two hinged pieces of plastic and a disc tray insert. Slimline cases are jewel cases that have half the depth of a standard case. J cases are like slimline cases, but are molded to fit the disc instead of using an insert. A slim double case is like a standard jewel case, but has a thin piece of plastic in the middle that holds discs on both sides instead of an insert.
A chubby case takes up the space of two standard jewel cases and has two insert-side parts of a standard jewel case held together by a thick plastic divider that the insert-sides face when closing. Some chubby cases use the divider to store two additional discs. There are versions of the chubby case that use a series of plastic mounts to hold six or more discs. Jewel cases may also come with a cardboard sleeve that covers the outside.
Paper cases are often used for retail CDs, but not as frequently as jewel cases. A Digipak is a paper-folding version of the standard jewel case with a plastic tray. FLPak cases are like Digipak cases, except they feature a plastic locking mechanism to hold the case closed. A DiscBox slider is a thin cardboard sleeve that uses a sliding piece of cardboard to close the case and slide the disc out when opened. A JakeBox case is a paper case that resembles a pop-up book. When the case is opened, the paper inside folds out and lifts the disc. Paper sleeves hold discs like envelopes and can feature a see-through plastic window to help view the disc inside.
Plastic cases are usually designed to protect CDs and are bought separately from the discs themselves. The clamshell case is a durable folding piece of plastic that is molded around the edges of a disc. Clamshell cases can extend just beyond the edge of the disc or have an extended edge. PolyBox cases are like plastic versions of the chubby-style jewel cases. A DiscSaver case is a single durable plastic case that is shaped like a slimline case, but the disc is inserted into a sleeve.