Software holders are devices that store software, such as DISCS, PCs, croms, disks, and CDROMs. DISCS are round, flat pieces of plastic with data stored on them, usually used for music or video. PCs are personal computers, which are computers designed for individual use. Croms are a type of memory chip used in computers. Disks are similar to DISCS, but they are usually made of metal and have a hole in the middle. CDROMs are optical DISCS that can store large amounts of data.