| Word or
Term |
Description or
Explanation |
| Tag |
a code embedded in an HTML document to tell Web
browsers how to display a portion of the text or an image |
| Tapestreamer |
computer data has, for many years, been stored
on magnetic tape - this is a basically inefficient method in the sense that if
you are at one end of the tape and the data you want is at the other end, it
can take a long time to reach the information - however, it is very efficient
in the sense that the medium, magnetic tape, can be very inexpensive per
megabyte - atapestreamer is a glorified (video) tape recorder controlled by the
computer and is used mainly for backup storage purposes |
| Task manager |
this is the Acorn icon at the far right of the
iconbar - it is an application that controls the allocation and use of memory
within the computer |
| TCP |
Transmission Control Protocol - the protocol
which sits above IP and implements a reliable connection between two hosts
using the unreliable packet transmission capabilities of IP - data is passed
down to TCP from the application protocols above i t is TCP's job to fragment
each message into chunks which will conveniently fill an IP packet, labelling
each chunk appropriately - at the other end of the connection, the remote
host's TCP must reassemble the original message from the packets it receives
from IP below and pass it up to the correct application protocol - if any of
the chunks is missing, it must ask the other end to resend the lost ones - in
this way, TCP simulates a direct connection between two hosts because messages
sent in at one end will eventually pop out at the other end, in the same
order |
| TCP/IP |
Transfer Control Protocol / Interface Protocol
- this is a standard protocol for transferring data between different computers
on a LAN or via modem link |
| Telnet |
logs on to a remote machine, giving two-way
communication so you can type commands and get the screen output back |
| Telnet port |
if a machine has several different tasks or
services accessible on Telnet, each will be accessed through a port - each port
is identified by a four-digit number |
| Template |
a set of windows and dialogue boxes that have
been designed for use within an application |
| Terminal emulator |
a program that allows your computer to pretend
that it is an unintelligent box capable of sending and receiving textual
information - Telnet is accessed by a terminal emulator |
| TeX |
a typesetting language, allowing you to typeset
complex mathematical documents (and more humble text documents) from the
command line |
| TFT |
Thin Film Transistor - a superior type of LCD
screen, also referred to as an 'active matrix display', often used for portable
computer displays - each of the screen's pixels is controlled by its own
transistor, affording an enhanced resolution and refresh rate |
| Thin client |
a simple client program or device which relies
on most of the functionality of the system being located in the server |
| by the mid-1990s, it was thought that the model
of decentralised computing, where each user has his own full-featured and
independent microcomputer, had won over a centralised model where multiple
users use thin clients (e.g. dumb terminals) to do work on a shared
minicomputer or mainframe server - networked personal computers typically
operate as "fat clients", often providing everything except some file storage
and printing locally |
| reintroduction of thin clients is being
proposed, especially for LAN-type environments - the main expected benefit of
this is ease of maintenance: with fat clients, especially those suffering from
the poor networking support of Microsoft operating systems, installing a new
application for everyone is likely to mean having to physically go to every
user's workstation to install the application, or having to modify client-side
configuration options; whereas with thin clients the maintenance tasks are
centralised on the server and so need only be done once |
| also, by virtue of their simplicity, thin
clients generally have fewer hardware demands, and are less open to being
screwed up by over-ambitious users |
| Thread |
a series of linked messages forming a
discussion within a newsgroup that is all on the same subject - normally, a
followup article will have the Subject line preceded with "Re:" - for example,
in the newsgroup comp.sys.acorn.hardware, there might be a thread with the
subject line "Re: Acorn's new machines" |
| Thumb |
an extension of the 32-bit ARM architecture -
the Thumb instruction set features a subset of the most commonly used 32-bit
ARM instrucxtions compressed into 16-bit wide op-codes - processors that are
'Thumb-aware' are aimed at embedded control applications, e.g. laser printers,
modems etc. |
| TIFF (files) |
Tagged Image File Format - a very versatile
format for storing and transferring bit-mapped graphics |
| Time |
Time Protocol (RFC 868 -
http://www.faqs.org/rfcs/rfc868.html) provides a machine-readable date and
time. It can be either TCP or UDP on port 37. Date and time are sent as a
32-bit binary number |
| Title bar |
the bar along the top of a window that contains
the name of that window |
| TLB |
Translation Look-aside Buffer - this is part of
an ARM processor which helps it to access different areas of memory more
quickly - basically, it's the bigger the buffer the better! |
| Toggle size icon |
the icon at the top righthand corner of a
window that is used to extend and contract a window between its maximum size
and the size and position to which you last reduced it |
| Tokenised |
when a Basic program is stored, it is usually
stored with each keyword represented by a single byte rather than as a string
of ASCII codes - these single bytes are referred to as tokens |
| Toner |
this is the pigment, in the form of a fine
powder, used in a laser printer (or photocopier) |
| Toolbox |
a window or pane of tool icons - it may be
free-standing or attached to another widow |
| TPI |
Tracks Per Inch - this is one way of specifying
the amount of data you can store on your floppy discs, e.g. 800Kb 3½"
discs (DD) are 135tpi |
| TPoP |
Traditional PoP - Demon only have a few of
these left - they have there own set of modems and computers to log you in |
| Tracking |
in some applications, the spacing between
individual letters within a block of text can be controlled - this is called
tracking - if the tracking is changed, the spacing between all the characters
is increased or decreased - this is distinct from kerning which relates to the
spacing between individual pairs of characters |
| Trackpad/point |
a pointing device replacing the conventional
mouse, which allows the pointer to be moved by sliding a finger around a
touch-sensitive surface - tapping the pad emulates the mouse select button |
| Transparency
mask |
an optional part of a sprite that defines which
pixels of that sprite are transparent |
| TRM |
Technical Reference Manual - term used to refer
to the optional hardware manual for Acorn computers |
| Trojan |
a sort of virus although it does not replicate
itself - it is something which is hidden in a file and, when activated, it does
terrible damage ... like a Friday 13th thingy - obviously named after the
Trojan Horse |
| Trojan horse |
a program that pretends to do, or does,
something useful, but which contains code that does something else - this can
range from printing silly messages on your screen to trashing your hard drive -
it's the network equivalent of a virus |
| Troll |
a newsgroup post that is deliberately
incorrect, intended to provoke readers; or a person who makes such a post |
| TSV |
Tab Separated Variables - a standard way in
which data is stored in a file where the items of data are separated by tab
characters |