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Glossary
ACPI (Advanced Configuration and Power Interface):
a power management
specification that allows the operating system to control the amount of power
distributed to the computer’s devices. Devices not in use can be turned off, reducing
unnecessary power expenditure.
AGP (Accelerated Graphics Port):
a PCI-based interface which was designed
specifically for demands of 3D graphics applications. The 32-bit AGP channel
directly links the graphics controller to the main memory. While the channel runs at
only 66 MHz, it supports data transmission during both the rising and falling ends of
the clock cycle, yielding an effective speed of 133 MHz.
ATAPI (AT Attachment Packet Interface):
also known as IDE or ATA; a drive
implementation that includes the disk controller on the device itself. It allows CD-
ROMs and tape drives to be configured as master or slave devices, just like HDDs.
ATX:
the form factor designed to replace the AT form factor. It improves on the AT
design by rotating the board 90 degrees, so that the IDE connectors are closer to
the drive bays, and the CPU is closer to the power supply and cooling fan. The
keyboard, mouse, USB, serial, and parallel ports are built-in.
Bandwidth:
refers to carrying capacity. The greater the bandwidth, the more data
the bus, phone line, or other electrical path, can carry. Greater bandwidth, then,
also results in greater speed.
BBS (BIOS Boot Specification):
is a feature within the BIOS that creates,
prioritizes, and maintains a list of all Initial Program Load (IPL) devices, and then
stores that list in NVRAM. IPL devices have the ability to load and execute an OS,
as well as provide the ability to return to the BIOS if the OS load process fails for
some reason. At that point, the next IPL device is called upon to attempt loading of
the OS.
BIOS (Basic Input/Output System):
the program that resides in the ROM chip,
and provides the basic instructions for controlling your computer’s hardware. Both
the operating system and application software use BIOS routines to ensure
compatibility.
Buffer:
a portion of RAM which is used to temporarily store data, usually from an
application, though it is also used when printing, and in most keyboard drivers. The
CPU can manipulate data in a buffer before copying it, all at once, to a disk drive.
While this improves system performance --- reading to or writing from a disk drive a
single time is much faster than doing so repeatedly --- there is also the possibility of
losing your data should the system crash. Information stored in a buffer is
temporarily stored, not permanently saved.