88
Appendix B : Glossary
Hard disk.
Fixed storage media along with integrated electronics that consists
of several magnetic platters that rotate synchronously on one spindle. Hard
disks have relatively high capacity and high read/write speed.
Hard disk geometry.
A set of hard disk parameters that usually includes the
number of cylinders, heads and sectors per track.
Head (magnetic head, read/write head).
A hard disk consists of several magnetic
platters, for each side of each platter there is a head that is used to read and
write information on it.
Hidden partition.
A partition that is made invisible to the operating system.
Usually partitions are hidden by changing their type.
Label.
An optional name that can be assigned to a partition to simplify its
identification. Usually has the same limitation as file names. For example,
FAT partitions have labels up to 11 characters long, but may contain spaces.
Large hard disk support software.
Some BIOS versions have troubles
supporting large (larger than 8 gigabytes) hard disks. That is why some hard
disk manufacturers provide special software that is installed in the beginning
of the hard disk, is loaded before any operating systems, and substitutes
hard disk access BIOS functions.
Letter (of a drive, partition).
All operating systems that are somehow
DOS-compatible use Latin letters to identify drives and partitions. Letters A:
and B: are usually reserved for floppy drives. Starting with C: letters are
assigned to hard disk partitions that can be recognized by the operating
system. Separate letters may be assigned to CD-ROMs, to DVD drives, or to
network drives.
Logical disk
is a partition whose file system is recognized by the operating
system. Usually each logical disk is assigned with a letter that uniquely
identifies it.
Logical partition.
Partition information which is located not in MBR, but in the
extended partition table. The number of logical partitions on a disk is
unlimited.
Master Boot Record (MBR)
is a special place in the very first sector of the hard
disk to store information about the hard disk partitioning and code to be
loaded with BIOS. All the actions that follow depend on the contents of this
code.
Operating system
is a set of programs that usually includes kernel, drivers,
shell, and system programs that are used for centralized hardware
management and hiding the details of hardware management from the user
and applications.