Specifications

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Appendix A Glossary
Wi-Fi Protected Access (WPA) A Wi-Fi
Alliance standard designed to secure wireless net-
works, which is much more secure than the previ-
ous WEP standard.
wide area network (WAN) A LAN that
extends beyond the boundaries of a single building.
Winchester drive Any ordinary, nonremovable
(or fixed) hard disk drive. The name originates from
a particular IBM drive in the 1960s that had 30MB
of fixed and 30MB of removable storage. This 30-30
drive matched the caliber figure for a popular series
of rifles made by Winchester, so the slang term
Winchester was applied to any fixed-platter hard
disk.
Winchester technology The term Winchester is
loosely applied to mean any disk with a fixed or
nonremovable recording medium. More precisely,
the term applies to a ferrite read/write head and
slider design with oxide media that was first
employed in the IBM 3340 disk drive, circa 1973.
Virtually all drives today actually use developments
of Whitney technology.
Wintel The common name given to computers
running Microsoft Windows using Intel (or com-
patible) processors. A slang term for the PC stan-
dard.
wire frames The most common technique used
to construct a 3D object for animation. A wire
frame is given coordinates of length, height, and
width. Wire frames are then filled with textures,
colors, and movement. Transforming a wire frame
into a textured object is called rendering.
wireless access point (WAP) A wireless trans-
ceiver that acts as a communications hub for net-
work access. Usually included with a router in the
form of a wireless router.
wireless local area network (WLAN) A local
area network with at least one wireless access point.
word length The number of bits in a data char-
acter without parity, start, or stop bits.
workstation 1) A somewhat vague term describ-
ing any high-performance, single-user computer
that usually has been adapted for specialized graph-
ics, computer-aided design, computer-aided engi-
neering, or scientific applications. 2) A computer
connected to a server.
World Wide Web (WWW) Also called the
Web. A graphical information system based on
hypertext that enables a user to easily access docu-
ments located on the Internet.
WORM (write-once, read-many or multiple)
An optical mass-storage device capable of storing
many megabytes of information but that can be
written to only once on any given area of the disk.
A WORM disk typically holds more than 200MB of
data. Because a WORM drive can’t write over an old
version of a file, new copies of files are made and
stored on other parts of the disk whenever a file is
revised. WORM disks are used to store information
when a history of older versions must be main-
tained. Recording on a WORM disk is performed by
a laser writer that burns pits in a thin metallic film
(usually tellurium) embedded in the disk. This
burning process is called ablation. WORM drives are
frequently used for archiving data. WORM drives
have been replaced by CD-R drives, which have
a capacity of 650MB–700MB but have similar
characteristics.
write precompensation A modification
applied to write data by a controller to partially
alleviate the problem of bit shift, which causes
adjacent 1s written on magnetic media to read as
though they were farther apart. When adjacent 1s
are sensed by the controller, precompensation is
used to write them more closely together on the
disk, thus enabling them to be read in the proper
bit cell window. Drives with built-in controllers
typically handle precompensation automatically.
Precompensation usually is required for the inner
cylinders of now-obsolete oxide media drives.
write protect Preventing a removable disk or
Sony Memory Stick from being overwritten by
means of covering a notch or repositioning a slid-
ing switch, depending on the type of media.
X2 A proprietary modem standard developed by
U.S. Robotics (since acquired by 3Com) that
enables modems to receive data at up to 56Kbps.
This has been superseded by the V.90 standard. See
also V.90 and V.92.
x86 A generic term referring to Intel and Intel-
compatible PC microprocessors. Although the
Pentium family processors do not have a numeric
designation because of trademark law limitations
on trademarking numbers, they are later genera-
tions of this family.
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