| Word or
Term |
Description or
Explanation |
| BABT |
British Approvals Board for Telecomunications -
the standard for telecoms equipment that can be used in UK |
| Baby Bells |
the local telephone companies in the United
States - originally, there was one large Phone company in the US - AT&T -
in the mid-1980's, AT&T broke itself up - there became two companies:
AT&T (the one we know now) which handled all long distance phone lines and
connections, and a number of smaller companies which handled the local calls -
this group of smaller companies (there were about six), came to be collectively
know as the Baby Bells (AT&T's nickname before breaking up was Ma
Bell) |
| some of the Baby Bells have merged, some have
sold out to other companies, and generally things have changed - also, the Baby
Bells want to provide long distance phone calls (something they couldn't do
originally) - as a result, AT&T (the one which handled long distance calls
after the break up) wants to be able to provide local calls (something it can't
do) - the effect of this, and the explosion in the number of phone companies,
means that the situation will be constantly changing for a few years yet - not
to mention Internet Telephony which threatens to decimate long-distance voice
traffic, but explode the amount of data-traffic piped round the planet |
| Back icon |
the icon at the top lefthand corner of a window
which allows you to push the window to the back of the desktop |
| Backbone |
a high-speed interconnection carrying large
volumes of data traffic to more local, slower speed interconnections - in the
U.S., the backbone of the Internet is often considered the NSFNet, a government
funded link between a handful of supercomputer sites across the country |
| Backdrop |
this is a desktop background which may be a
sprite or just a pattern |
| Backplane |
a small printed circuit board with connectors
on it that allows you to plug in a number of expansion cards |
| Bandwidth |
the rate at which data can be sent through any
given data connection - usually expressed in Mbit/s (megabits per second) |
| BASH |
Bourne-Again Shell - an improved version of the
Bourne shell, the original Unix command shell written by a Mr. Bourne |
| Basic |
Beginners All-purpose Symbol Instruction Code -
a commonly-used interpreted high level language - it comes as standard on all
Acorn computers |
| Baud |
this is a unit of speed for serial data
transmission. (Rough definition...)1 baud = 1 binary bit per second. 1 Kilobaud
(Kbaud) is 1024 bits/second = 128 bytes/sec (assuming 8 bits per byte) -
however, over a telephone line, because each byte tends to have associated
'start' and 'stop' bits, 1 Kilobaud is more like 100 bytes/sec or
6Kbytes/minute - on this basis, a high speed modem at 28.8 Kbaud can transmit
about 3Kbytes/sec or 200Kbytes/minute, however, using compression techniques,
this can be increased somewhat - the more expensive modems use systems, such as
Microcom Network Protocol (MNP), which can correct for errors and which
compress data to speed up transmission |
| to be more technically correct... Baud is not
the same as bits per second but is 'the number of discrete conditions or signal
elements transmitted per second' - for example, V.22bis is transmitted at 600
baud, but 2400 bps - this is because it is using what is called PSK (Phase
Shift Keying) - here you can have each baud in four different phases: 0°,
90°, 180°, and 270° - so, for each baud you can have four different
states, and this means you can transmit 4 bits per second per baud |
| BBS |
Bulletin Board Service/System - a bulletin
board is an application run on a computer which stores information and messages
that can be accessed by other computers, usually via the telephone line using a
modem - many bulletin boards allow a number of other computers to connect to
the host computer at the same time by using a number of different modems and
phone lines |
| BCC |
Blind Carbon Copy - an email header listing
recipients to whom a copy of the message should be sent - unlike CC, no
recipients will see this list |
| Bezier curves |
mathematically defined curves used (amongst
other things) by RISC OS to create outline font shapes |
| Big Eight, The |
was The Big Seven - the main Usenet
hierarchies: comp, humanities, misc, news, rec, sci, soc and talk (humanities
was added in 1995, so you may see references to the Big Seven) |
| Binary |
the number system (base 2) used as the basis of
most computer systems |
| Binary data (file) |
data that consists of more than just textual
information - alphanumeric text can be represented using a limited range of
ASCII codes from 32 to 127 with some of the numbers below 32 used as control
codes such as 10 for linefeed and 12 for formfeed/clear screen - binary data,
by contrast, uses all the codes 0 to 255 and, if it were transmitted as if it
were a text file, the control codes could have all sorts of undesired effects -
other techniques therefore have to be used for its transmission, e.g.
uuencoding |
| BIOS |
Basic Input/Output System - this is the part of
a PC compatible's operating system that is held in ROM, allowing the computer
to start up and load the rest of its operating system from disc (c.f. RISC OS
computers where the whole of the operating system, plus a few extra goodies,
are held in ROM and are available at switch-on) |
| Bison |
the Free Software Foundation's version of yacc |
| Bit |
binary digit - a bit is the smallest unit of
binary data - it has two values, 0 and 1 - a group of 8 bits of data (referred
to as a byte) could be used to represent a single character using, most
commonly, the ASCII code or it could represent (part of) an instruction that
the computer would execute at some stage or it could represent (part of) a
number |
| Bit-mapped
graphics |
it is possible to represent a picture on a
computer by using a matrix of (coloured) dots - the resolution of bit-mapped
pictures is limited by the numbers of dots used (this contrasts with
Vector graphics - for example,
the Paint application produces bit-mapped graphics whereas Draw produces vector
graphics) |
| Bitnet |
Because It's Time Network - the American
academic network - the equivalent of Janet in the UK - it is based on IBM
mainframes, and therefore uses EBCDIC character codes |
| Bluetooth |
Bluetooth Special Interest Group,
http://www.bluetooth.com - a consortium of computer and telecommunications
companies founded in 1998 by Ericsson, IBM, Intel, Nokia and Toshiba - it
supports an open specification for wireless, short-range transmission between
mobile PCs, mobile phones and other portable devices |
| Bluetooth provides up to 720 Kbps data transfer
within a range of 40 feet - unlike IrDA which is a line of sight technology and
requires that the devices be aimed at each other, Bluetooth uses radio waves,
which are omnidirectional and can transmit through walls. - the technology uses
the 2.4GHz Industrial Scientific Medical (ISM) frequency band, which is not
licensed by the FCC - this set of frequencies is used by other wireless LANs
and telecommunications systems - when there is interference from other devices,
the transmission does not stop, but its speed is downgraded. Bluetooth products
are expected by the end of 1999 |
| the name Bluetooth comes from King Harold
Bluetooth of Denmark - in the 10th century, he began to Christianize the
country. Ericsson (Scandinavian company) was the first to develop this
specification - see IrDA |
| BMP file |
Bit MaP file - also known as a "bump" file, it
is a Windows and OS/2 bitmapped graphics file format - it is the Windows native
bitmap format, and every Windows application has access to the BMP software
routines in Windows that support it. BMP files provide formats for 2, 16, 256
or 16 million colors (1-bit, 4-bit, 8-bit and 24-bit colour). BMP files use the
.BMP or .DIB extensions (DIB stands for Device-Independent Bitmap) |
| BNC connectors |
the bayonet-type (push-and-twist) connectors
used in Ethernet installations |
| Boot |
short for Bootstrap, the name given to an
automatic program loading process when a computer is switched on, or a program
run |
| Bot |
an artificial intelligence usually found
masquerading as a human user, carrying out repetitive or tedious tasks like
responding to email (presumably an abbreviation for robot) |
| Bounce |
an item of email is said to have bounced when
it fails to find its recipient and is returned to the sender, sometimes with a
message explaining why it was unable to be delivered |
| Bourne shell |
the original Unix command shell written by a
Mr. Bourne |
| bpp |
bits per pixel - the number of bits used to
store the colour of each pixel |
| bps |
bits per second - see Baud |
| Bridge |
a computer or other dedicated hardware that
links two networks of the same type together and does some filtering of packets
from one network to the other and vice versa |
| Broadband |
a term referring to connections to the internet
from homes and small businesses, offering an always on, relatively high
bandwidth connection - provision is either via a telephone line (a technology
known as ASDL) or a cable modem such as the ntl:world system |
| Browser |
a program that allows you to access the
worldwide web (WWW) |
| Bubblejet printer |
this is a type of inkjet printer where the
patterns on the paper are generated by squirting ink through a series of tiny
nozzles in the print head - functionally, it is the same as an inkjet printer -
the ink near the end of the nozzle is heated so that it expands and squirts a
small volume of ink out onto the paper |
| BubbleJet |
registered to Canon in 1977 - they are a
variety of inkjets and use very similar systems, although only Canon can use
the BubbleJet name |
| Bug |
error in a computer program |
| Bullet |
a large black dot used to highlight something
within some text |
| Bulletin board |
see BBS |
| Bus |
a set of parallel wires or PCB tracks along
which data is transmitted in a computer system - the width of the bus refers to
the number of parallel tracks - the wider the bus, the faster data can be
transmitted down it |
| Byte |
a byte refers to 8 bits of binary data stored
within a computer's memory or on a data storage medium |