Technical information

ICT in the science department 1654 © CLEAPSS 2005
POP Post Office Protocol. A protocol for servers and clients used to process e-mail.
Port That part of a computer through which information may be passed to and from attached
hardware.
Portal A web site that acts as a gateway to other web sites and resources related to a particular
subject or topic.
Port replicator Similar to a docking station.
Postscript A language used to describe a page of text and graphics for print.
Print queue A buffer for documents waiting to be printed.
Procedure A sequence of commands forming a simple operation; part of a computer program.
Program A sequence of commands and procedures which tell the computer how to solve a
problem or perform a required task.
Prompt Text that is displayed to indicate that a program or shell is awaiting user input.
Protocol A set of rules or standards that enable computers to exchange data.
Proxy A computer or software that is connected to the Internet and then delivers that connection
to computers on an internal network. Thereby it provides a single point at which to apply a
firewall and it hides internal network computers to an extent since only the proxy is
revealed to the external Internet.
PSTN Public Switched Telephone Network.
Public domain Software or information that is not copyright and is free for public use.
Query A set of instructions used to extract desired records from a database or other program.
QuickTime
player
Apple’s audio / video playback application. PC- and Mac-compatible versions are
available. Associated file extensions are .mov and .qt. Includes a picture viewer that can
display Mac image formats on a PC.
RAM Random Access Memory: the internal electronic store that the computer uses to
temporarily hold data and programs whilst they are in use. The data may be accessed in
any order.
Raster graphics Graphics generated as a collection of individual dots (pixels) arranged in rows and
columns.
RAW An image file format that is essentially the untouched data captured by a digital camera
sensor. Typically only available with high-end digital cameras.
RCA Radio Corporation of America; originally an audio (phono) connection but now also used
for video.
Real Player Audio / video playback application from RealNetworks. Also caters for online streaming
media. Associated video file formats are .ram, .rmm, .ra, .rax, .rv, .rvx, .rm, .rmx, .rmj
and .rms.
Record A data structure consisting of one or more fields relating to a single entity.
Refresh rate The rate at which a computer’s display is redrawn.
Region code A code that defines the region of the world in which a DVD or movie can be shown.
Register Small, fast memory device that has a specific address and that is used to hold information
of a specific type or for a particular purpose.
Relay An electromagnetically-operated switch that, when in a circuit, can switch an entirely
independent circuit.
Resolution A measure of the accuracy of detail produced on a computer monitor or a printer. For a
computer display, it is typically represented as the number of pixels displayed horizontally
and vertically, eg, 1280 x 1024 pixels or 1.3 megapixels. In print, the measure is dpi or
dots per inch.
RF Radio Frequency. Refers to electromagnetic signals of frequencies up to 300 GHz. An RF
current can be converted by a suitable transmitter into an electromagnetic field that can
travel through the air. This enables data to be transmitted via ‘wireless connection’. For
example, television signals.