Data and programs are stored in units called files on secondary storage media such as hard disks, floppy diskettes, and compact disks (CDs). Each file is given a name by which it can be accessed. A secondary storage medium is often organized so as to include several folders, where a folder is a container for files. Each folder has a directory specifying the names of the files stored in it. A set of related files, such as those giving students addresses, grades, and hobbies, is referred to as a database.
