Maxtor ATLAS 10K III Product Manual page 268

Glossary
BEZEL – A plastic panel that extends the face
of a drive so that it covers a computer's drive
bay opening. The bezel usually contains a drive-
activity LED. Also known as the faceplate.
BIT – Abbreviation for binary digit. A binary
digit may have one of two values—1 or 0. This
contrasts with a decimal digit, which may have
a value from 0 to 9. A bit is one of the logic 1or
logic 0 binary settings that make up a byte of
data. (See also .)
byte
BLOCK – In UNIX workstation
environments, the smallest contiguous area that
can be allocated for the storage of data. UNIX
blocks are generally 8 Kbytes (16 sectors) in size.
In DOS environments, the block is referred to
as a cluster. (Note: This usage of the term block
at the operating system level is different from its
meaning in relation to the physical
configuration of the hard drive. See
comparison.)
BPI – Bits Per Inch. A measure of how densely
information is packed on a storage medium.
(See also .)
FCI
BUFFER – An area of RAM reserved for
temporary storage of data that is waiting to be
sent to a device that is not yet ready to receive
it. The data is usually on its way to or from the
hard disk drive or some other peripheral device.
BUS – The part of a chip, circuit board, or
interface designed to send and receive data.
BYTE – The basic unit of computer memory,
large enough to hold one character of
alphanumeric data. Comprised of eight bits.
(See also .)
bit

CACHE – Specialized High-speed RAM used
to optimize data transfers between system
elements with different performance
characteristics, e.g., disk to main memory or
main memory to CPU.
CAPACITY – The amount of information that
can be stored on a hard drive. Also known as
storage capacity. (See also
G-2
Maxtor Atlas 10K III 18/36/73 GB Ultra160 SCSI
for
sector
.)
formatted capacity
CLEAN ROOM – An environmentally
controlled dust-free assembly or repair facility
in which hard disk drives are assembled or can
be opened for internal servicing.
CMOS – Acronym for complementary metal
oxide semiconductor. A low-power, low-heat,
high-density semiconductor.
COMMAND QUEUE – The queue used to
store I/O processes.
CONNECT – The initiator function that
selects a target to establish a nexus and to start
an I/O process. The connection that results is
an initial connection.
CONNECTION – An initial connection or
reconnection that can occur only between one
initiator and one target.
CONTINGENT ALLEGIANCE – A
condition generated by a CHECK
CONDITION or
COMMAND TERMINATED status during
which execution of all tagged I/O processes (for
the associated I_T_X nexus) are suspended until
the condition is cleared. A target preserves an
I_T_X nexus until it is cleared by a hard or soft
reset, an abort message or another command for
that I_T_X nexus. While the contingent
allegiance condition exists, the target maintains
sense data for the initiator.
CLUSTER – In DOS environments, the
smallest contiguous area that can be allocated
for the storage of data. DOS clusters are usually
2 Kbytes (4 sectors) in size.
CONTROLLER – The chip or circuit that
translates computer data and commands into a
form suitable for use by the hard drive. Also
known as disk controller.
CONTROLLER CARD – An adapter
containing the control electronics for one or
more hard disks. Usually installed in a slot in the
computer.
CPU – Central Processing Unit. The
microprocessor chip that performs the bulk of
data processing in a computer.