Hard Drive: The Hard Drive is usually inside the case with the CPU. This is a drive that stores most of your programs and files. They come in various sizes. Some computers have more than one hard drive.

Floppy Disk / Diskette Drive: The Diskette Drive can come in two sizes, but 3.5" diskettes are far more common.

CD-ROM: The CD-ROM Drive is a drive to run CD-ROMs. It looks much like an audio CD player. This drive can again be in the CPU case or attached as a peripheral device. It has a button that you push to open and close the drawer, which has a circular slot that you put the CD into. Some computers don't have CD drives.