Storage Structure

• Sometimes, it is desirable to place multiple file systems on a disk or to use parts of a disk for a file system and other parts for other things, such as swap space or unformatted (raw) disk space.
• These parts are known variously as partitions, slices, or (in the IBM world) minidisks.
• A file system can be created on each of these parts of the disk. We simply refer to a chunk of storage that holds a file system as a volume.
• Each volume that contains a file system must also contain information about the files in the system. This information is kept in entries in a device directory or volume table of contents.
• The device directory (more commonly known simply as a directory) records information-such as name, location, size, and type-for all files on that volume. Figure 10.10 shows a typical file-system organization.

  Figure 10.10: A typical file-system organization.