Wavelength
: Wavelength is the physical distance spanned by
one complete cycle or wave of an alternating signal as it travels
through space. The term wavelength can be applied to many types of
wave, e.g. audio, radio, light, etc, but is generally only
applicable to a wave of a single frequency, such as the RF carrier
transmitted by a mobile phone. Wavelength (l), usually measured in
metres between the adjacent peaks or troughs of consecutive waves,
is related to frequency (f) and propagation velocity (v) by the
equation l = v / f. Note that the propagation velocity depends on
the type of wave and the material through which it passes: radio
waves travel at the speed of light, but audio waves at the speed of
sound |
|
Web authoring software
: A computer programme designed to produce web
pages for a web site. |
|
Web Page
: A web page or webpage is a
resource on the World Wide Web |
|
Web site Web pages
: A collection of related pages (web pages) of
information, owned and maintained by the same organisation or
individual, and published on the Internet. It is relatively
straightforward for schools and individuals to create a web
site. |
|
Whiteboard/interactive, electronic
: Like a conventional whiteboard, except that
the images from the computer are projected onto the board and can
be controlled and adjusted on screen using a stylus. Can be used in
whole class teaching. |
|
WIM
: Also known as: WAP identity module WIM (WAP
identity module) is a security module that provides a more secure
environment when using WAP related applications and services on a
mobile device via a WAP gateway. A WIM allows the user to store
certificates and digital signatures |
|
Wireless Application Protocol
: Also known as: WAP WAP (Wireless Application
Protocol) is a common global standard, which defines the way in
which Internet communications and advanced non-voice services are
provided on wireless mobile devices, such as digital mobile phones
and Personal Digital Assistants. The current version of this
protocol is WAP 2.0, and it is fast becoming the standard way for
mobile devices to access Internet services, by communicating with a
server installed in the mobile phone network. A mobile device can
therefore combine telephony services with the limited capacity of
mobile terminal displays, and so provide the user with a
microbrowser. A WAP enabled phone provides interactive access to
the Internet, and to services such as online news and information,
e-commerce transactions, online banking, e-mail messaging, Internet
Relay Chat (IRC), and a host of new services still in development.
Subscribers use WAP to access websites and pages that have been
converted for WML (Wireless Markup Language), which are stripped
down to their basic text format, and this is more suitable for the
limited display capabilities of mobile devices. WAP works with
multiple standards and is supported by most modern mobile networks,
such as GSM, GPRS, and UMTS, and in the future equipment and
networks that use WAP will be more compatible, regardless of the
manufacturer. WAP is the mobile equivalent of HTTP (HyperText
Transfer Protocol), and has been developed through the cooperation
of the world's major telecommunications and software companies,
their activities being co-ordinated through the WAP Forum. The WAP
Forum has a website at www.wapforum.org. Some manufacturers claim
that their handsets have WAP 2.0 browsers; this is often a
re-branding of an XHTML-MP browser, the version number representing
XHTML replacing WML for mobile content markup. An alternative
system standard to WAP is i-Mode |
|
Wireless Phone
: Wireless Phone is another name for a mobile
phone. The word 'wireless' refers to the fact that the phone is
actually a small radio transceiver, which communicates with the
mobile telephone network by transmitting and receiving radio
signals through the air without using wires. Although the various
types of mobile phone, cell (cellular) phones, and car phones are
all wireless devices, the cordless phones used at home are not
considered wireless, as their base units are connected by wires to
the network |
|
Word processing
: The ability to enter, edit, manipulate, store
and print pages of text using a computer. Modern word processors
have desktop publishing capability. |
|
World Wide Web
: The vast collection of information which has
been published on the Internet in the form of web pages. |
|
Wristwatch monitor
: This consists of a strap fitting around your
chest that contains a radio that transmits your heartbeat to a
wristwatch monitor. Heart monitors can be programmed to beep if
your pulse rate moves outside your target zone. |
|
WYSIWYG
: what you see is what you get |
|
X-Modem
: Also known as: Ymodem Y-Modem is an
error-correction protocol used in the transfer of serial data files
between modems. Y-Modem is based on the earlier X-Modem protocol,
but has the additional feature of being able to cope with a batch
transmission mode, in which a number of files can be sent with one
command. For greater efficiency Y-Modem can also handle data with a
variable block size of up to a maximum 1024 bytes (1 kB). During
transmission, the size of text and binary files is included in the
Y-Modem header, so that the exact file length will be retained
after transfer. The error detection method in Y-Modem is cyclic
redundancy check (CRC). A later version of Y-Modem, Y-Modem-G,
transmits data in a continuous stream and does not acknowledge the
blocks successfully received; it is only the blocks with detected
errors that cause a negative acknowledgement (NAK), thus prompting
the resending of data |
|
XHTML
: XHTML (a merger of XML and HTML) is an updated
HTML standard introduced to help tidy up all the developments and
additions to original HTML. Over the years, different browsers
added features and offered increased functionality, which all had
their own proprietary manifestation in HTML. This led to a mish
mash of tags and markup that often led to web authors putting in
duplicate attributes and code in order to make sure that a page
looked the same in different browsers browsers. XHTML is a unifying
standard from the W3C that brings the XML benefits of easy
validation and troubleshooting to HTML, which not only helps
developers but also makes the pages easier to read for programs
such as mobile browsers. There are three variations of XHTML, the
most common of which is Transitional. XHTML Transitional is a
stepping stone from the deprecated HTML standardsL, and as such is
fairly permissive, allowing many old and proprietary attributes,
although Transitional stipulates that all tags must have both
opening and a closing markup and be correctly nested. XHTML Strict
is a more rigourous standard that removes all the ’chaff’ gathered
by HTML not ruled out in Transitional, and is what web authors
should strive toward. Finally, XHTML Frameset is similar to XHTML
Transitional, but allows for the use of frames. |
|
XML
: extensible markup language |
|
Y-Modem
: Also known as: Ymodem Y-Modem is an
error-correction protocol used in the transfer of serial data files
between modems. Y-Modem is based on the earlier X-Modem protocol,
but has the additional feature of being able to cope with a batch
transmission mode, in which a number of files can be sent with one
command. For greater efficiency Y-Modem can also handle data with a
variable block size of up to a maximum 1024 bytes (1 kB). During
transmission, the size of text and binary files is included in the
Y-Modem header, so that the exact file length will be retained
after transfer. The error detection method in Y-Modem is cyclic
redundancy check (CRC). A later version of Y-Modem, Y-Modem-G,
transmits data in a continuous stream and does not acknowledge the
blocks successfully received; it is only the blocks with detected
errors that cause a negative acknowledgement (NAK), thus prompting
the resending of data |
|
Z-Modem
: Also known as: Zmodem Z-Modem is an
error-correction protocol used in the transfer of serial data files
between modems. Z-Modem is a faster successor to Y-Modem and has
better error checking capability. Modems using the Z-Modem protocol
send data in 512-byte blocks or packets, and the error detection
method is cyclic redundancy check (CRC). Like Y-Modem, Z-Modem has
the capability of handling batch transmission (sending a number of
files with one command) and variable block sizes of data. Z-Modem
is also similar to Y-Modem-G, because it sends data in a continuous
stream, and does not require a positive acknowledgement (ACK) for
successfully transferred blocks of data. However, if an error is
detected in a received block, a negative acknowledgement (NAK) is
returned to the sender and the block resent. Z-Modem differs from
the earlier protocols in that it is able to recover after a
"crash", i.e. when a transmission is cancelled or for some other
reason interrupted, the transmission may be restarted without
resending the previously transferred blocks of data |
|