Specifications

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Appendix A Glossary
block diagram The logical structure or layout
of a system in graphics form. Does not necessarily
match the physical layout and does not specify all
the components and their interconnections.
Blu-ray Disc (BD) One of the two competing
high-definition DVD format standards. Also see
High Density Digital Versatile Disc (HD-DVD).
Blue Book The standard for enhanced CDs
(CD-E). CD-E media contains both music (for play
on standard CD players) and computer content.
Developed by Philips and Sony in 1995.
blue screen of death A system crash in
Windows that replaces the normal desktop with a
blue screen with white text reporting the problem
and locks up the system. Also referred to as a
BSOD, this condition can be triggered by defective
memory, file system errors, and other system
problems.
Bluetooth An emerging short-range networking
standard, Bluetooth is designed to enable PCs,
mobile phones, input devices, and PDAs to
exchange data with each other. Bluetooth uses the
same 2.4GHz frequency range used by some types
of wireless phones and by the IEEE 802.11b Wi-Fi
wireless Ethernet network. Bluetooth has a speed of
1Mbps or 2Mbps, depending on the version.
BMP A Windows graphics format that can
be device dependent or independent. Device-
independent BMP files (DIB) are coded for trans-
lation to a wide variety of displays and printers.
BNC (Bayonet-Neill-Concelman) Also known
as British-Naval-Connector, Baby-N-Connector, or
Bayonet-Nut-Coupler, this bayonet-locking con-
nector is noted for its excellent shielding and
impedance-matching characteristics, resulting in
low noise and minimal signal loss at any frequency
up to 4GHz. It is used in Ethernet 10BASE-2 net-
works (also known as IEEE 802.3 or Thinnet) to ter-
minate coaxial cables. It is also used for some
high-end video monitors. BNC is named for its
connection type (bayonet) and its co-developers.
bonding In ISDN, joining two 64Kbps B-channels
to achieve 128Kbps speed. Bonding can also be used
with analog modems that use the Multilink Point-
to-Point protocol, which is supported by Windows
98 and newer versions but by only a few ISPs.
Boolean operation Any operation in which
each of the operands and the result take one of two
values. A Boolean search can be performed with
many search engines used on websites and help
files using operators such as AND, OR, and NOT.
boot To load a program into the computer. The
term comes from the phrase “pulling a boot on by
the bootstrap.”
boot manager A program that enables you to
select which active partition to boot from. Often
supplied with aftermarket disk-partitioning pro-
grams, such as PartitionMagic, or installed by
default when you install a Windows upgrade into a
separate disk partition instead of replacing your old
version. See also active partition.
boot record The first sector on a disk or parti-
tion that contains disk parameter information for
the BIOS and operating system as well as bootstrap
loader code that instructs the system how to load
the operating system files into memory, thus begin-
ning the initial boot sequence to boot the machine.
boot sector See boot record.
boot sector virus A virus designed to occupy
the boot sector of a disk. Any attempt to start or
boot a system from this disk transfers the virus to
the hard disk, after which it subsequently is loaded
every time the system is started. Many older PC
viruses, particularly those spread by infected floppy
disks, are boot sector viruses.
bootstrap A technique or device designed to
bring itself into a desired state by means of its own
action. The term is used to describe the process by
which a device such as a PC goes from its initial
power-on condition to a running condition with-
out human intervention. See also boot.
boule Purified, cylindrical silicon crystals from
which semiconducting electronic chips, including
microprocessors, memory, and other chips, in a PC
are manufactured. Also called an ingot.
bps (bits per second) The number of binary
digits, or bits, transmitted per second. Sometimes
confused with baud.
branch prediction A feature of fifth-generation
(Pentium and higher) processors that attempts to
predict whether a program branch will be taken and
then fetches the appropriate following instructions.
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