advanced terms

Click on the first letter of the term to see a clear explanation of the common terms used about PCs.

A

Access  To gain entry to or connect to.

ADSL Asymmetric Digital Subscriber Line (Broadband): a broadband network connection with high-speed downloading but slower uploading (still faster than standard dial-up)
AGP Accelerated graphics port. An enhancement of the system bus designed to boost graphics performance.
Alphanumeric Consisting of letters, numbers and special characters such as punctuation marks or spaces.
Applications software for particular tasks, such as word-processors, graphics programs etc. provided on a computer in addition to the underlying operating system

Attachment A file (often in some special format, e.g. a word-processor file) attached to an email message  

B

Back slash The \ character. On most computer keyboards the back slash key is located near the top-right corner of the main section of the keyboard, although this is not always the case. The back slash character is frequently used when describing the location of a file, see as in:  C:\My Documents\My Music

Some computing old-timers use the terms slosh and slash for the forward slash (/) and the back slash (\) respectively. The slosh is used in Web addresses.

Backup A duplicate copy of a file. You should back up your data files regularly so you have a spare copy if the original is accidentally damaged or lost.
Bandwidth The amount of data that can be transmitted over a network connection at any one time. A standard modem connection to the Internet provides a relatively low bandwidth, making it unsuitable to download high-bandwidth media such as video; a cable modem provides considerably higher bandwidth.
BIOS Basic input/output system, pronounced buy-oss. Software built into your computer which controls basic communications, screen, keyboard and other functions. When your computer first starts up, it loads the BIOS before loading the operating system.
Bit Binary digit. The smallest piece of information that can be stored by a computer. A bit can have a value of 0 or 1. There are 8 bits in a byte.

Bluetooth Used for short-range wireless communication between devices, (e.g. between computers and mobile phones, wireless keyboards or mice) 
BMP  The BMP file format, sometimes called bitmap or DIB file format (for device-independent bitmap), is an image file format used to store bitmap digital images, especially on Microsoft Windows and OS/2 operating systems.

Bookmark A Web address recorded for future use (in Mozilla, Opera and other browsers: see also Favorites)

Boot To start up a computer.
Bps Bits per second, the standard measure of data transmission speeds.
Browser See Web browser.
Bug An error in a computer program or in computer hardware.
Bus A set of wires used to transfer data between the main components on a computer’s motherboard.

Bus Speed the speed at which the processor in a computer communicates with memory. Usual speed is 133MHz; it can be higher. 
Byte A measurement of memory. One byte can contain a single character – a letter, number, punctuation mark or other symbol. A byte contains eight bits.

C

Cable Modem A modem which operates over cable TV lines, providing high transmission rates.

Cache (a) a section of memory or a separate storage device used in a computer system to store recently accessed data or instructions

(b) (Proxy web cache): a collection of recently-fetched Web documents kept on a local proxy server, to reduce network traffic  

(c) (Local web cache): copies of recently-fetched Web documents kept locally (usually on the hard disk) by the web browser
CD-R Compact Disc Recordable. A drive that can create and read CD-ROMs and audio CDs. Also refers to the writeable compact disc media you place in a CD-R drive.
CD-ROM Compact Disc Read-Only Memory. A data version of the familiar audio CD. It has a fairly high capacity and is frequently used for program installations. The ‘read-only’ indicated that while you can read information from CD-ROMs you cannot write information to them.
CD-RW Compact Disc Rewriteable. A type of CD that lets you write to it in multiple sessions (unlike a CD-R disc which can be written to only once).
Central Processing Unit Also known as the CPU or microprocessor. The ‘brains’ of your computer. The CPU handles all the central logic and operations for your computer, assisted by other computer chips.
Chip Short for ‘microchip’. A small piece of silicon (or another semi-conducting material) which contains electronic components such as transistors and resistors organized into a circuit. Your computer contains many chips, including the central processing unit, memory chips, and other support chips.

Clipboard A special temporary storage space in memory. Whenever you use the cut or copy commands in a program, the information is stored on the clipboard. It may be inserted into the current document using the paste command. The clipboard can contain only one item at a time, so each copy or cut command will replace the current contents of the clipboard.
Configure To set up a computer system or computer program so that it functions well.
Cookie A small file placed on your hard disk by a Web site in order to identify you when you visit again.
CPU See central processing unit.
Crash A serious computer problem that causes a program to halt or the whole computer to stop working.
Cursor The small pointer that moves about the screen in a direct relationship to the movements of your mouse.
Cyberspace The non-physical world created within computer systems. When you’re connected to the Internet, for example, you are ‘in cyberspace’.

D

Data Any type of information. A letter you create with your word processor is data, as is a picture you draw using a graphics program. Data is stored on your computer in files.

Default A standard or recommended setting which you may alter if you wish. For instance, the Windows Taskbar appears at the bottom of your screen by default; you can move it to another position by dragging-and-dropping it.
Desktop The full-screen display where all Windows activity takes place. Analogous to a real desktop, where you place everything you’re currently working on.
Device Driver A piece of software which tells a piece of hardware how to work with the rest of a computer system. Your printer, for instance, requires a printer driver to make sure it works correctly.
Device Any computer sub-system or peripheral, such as a printer, USB port or disk drive.
Dialog box, dialog An onscreen box which lets you adjust settings or provide information needed to run a program, or which is used to alert you to some event. Dialog boxes require some form of interaction between the user and the computer, hence the name.
Dial-up connection A widely-used method of connecting to the Internet. A dial-up connection uses regular phone lines to connect one computer to another via modem.
Directory See folder.
Disable To prevent a feature or component from operating.
Disc A storage medium using optical technology. The term includes CD-ROMs, digital video discs and laser discs.
Disk A computer storage medium (using non-optical technology).
Diskette See floppy disk.

DNS Domain Name System (or Server): the mechanism that translates between domain names (e.g.www.cam.ac.uk) and IP addresses

Document Any self-contained piece of work created using a program. A letter you create with your word processor is a document; so, too, is a picture you create with a graphics editor or a Web page you design with a Web page editor.

Download To copy information from a remote computer to your computer. When you connect to the Web, you’re constantly downloading Web pages and files to your computer system.
Drop-down menu Sub-menus which drop down from another menu. Also known as cascading menus.
DSL Digital Subscriber Line. A technology that supports high-speed data connections.

Dual Boot A mechanism allowing a single machine to offer a choice of start-up operating systems (e.g. Windows and Linux)

DVD Digital Video Disc. A high-capacity CD-ROM storage disc.

DVI   Digital Video Interface: a way of connecting a flat screen

E

E-mail Electronic mail. Messages exchanged between users on a network.
E-mail address A unique name that identifies an e-mail recipient. E-mail addresses take the form username@hostname. An example is johndoe@morgue.com.au, which is pronounced ‘johndoe at morgue dot com dot a-u’. Note that e-mail addresses, unlike URLs (Internet addresses), are not case sensitive.
Enable To allow a program feature or a computer device to function.
Ergonomic Designed to enhance human comfort and performance.

Ethernet A very widely implemented technology for connecting computer systems in local-area networks
Execute To run a computer program.

F

FAQ Frequently Asked Questions (pronounced fak). Documents which give the answers to commonly asked questions about a particular topic.
Favorites A set of Web addresses recorded for future use (in Internet Explorer, Outlook and other browsers: see also bookmark)

File A collection of related information stored on a computer. Each document you create is stored in a file with its own filename, so you (and the computer) can identify it. Programs, too, are stored in files.

Firewall An application that lets you control and filter traffic on connections to or from your computer or network

FireWire The name used by Apple and others for a very fast external bus standard (IEEE 1394) for connecting external devices to computers. 1394 products for other systems are known as I. link and Lynx

Flame A vicious e-mail message or newsgroup posting in which the author attacks another online participant.
Floppy disk A small, removable storage medium. Floppies are so-called because inside the rigid protective case is a flexible, brown plastic disk on which data can be stored. To use a floppy, you insert it in a floppy disk drive.

Folder A file container on a disk. Like a folder in a filing cabinet, you can store related files in the same folder to help organize your information. 
FTP File Transfer Protocol. A commonly used method for transmitting files across the Internet.

G

GB See gigabyte.

GIF Graphics Interchange Format. A graphics file format used extensively on the Internet because it uses compression to minimize the size, and hence the download time, of the images. The format was originally developed by the online service provider, CompuServe. The letters gif are used as a file extension (the characters after the full stop/period in a filename) for files in the Graphics Interchange Format.
Gigabyte A measurement of memory. One gigabyte is equivalent to 2 to the 30th power (1,073,741,824) bytes or 1024 megabytes.

GUI Graphical User Interface, pronounced gooey. Windows is a GUI. That is, it is made up of graphical elements (windows, icons, menus). Contrast this with earlier operating systems such as DOS, which were purely textual, with commands entered by typing.

H

Hang See crash.
Hard disk A high-capacity, long-term storage medium.

Hard disk Known also as hard drive, hard disk drive or HDD.  It is a device where you permanently store programs and data. Hard disks are usually connected permanently with the main computer housing.
Hardware The physical equipment that makes up a computer system. Hardware is essentially the parts of a computer you can touch – the monitor, keyboard, disk drives, and so on.
Home page The main page of a Web site.
HTML Hypertext Markup Language, the authoring language used to create documents on the World Wide Web.

HTTP Hypertext Transfer Protocol. The set of rules governing the transmission of documents on the World Wide Web.
Hyperlink An element (piece of text, graphic image) in a document that links to another place in the same document or to an entirely different document. When you click a hyperlink, the link’s destination is fetched and displayed. The World Wide Web is composed of documents which use hyperlinks for interconnection. Text-based hyperlinks are often displayed in a different color or underlined, so they stand out from the rest of the document.

I

Icon A small on-screen picture which represents something: a program, a folder, a data file, a command shortcut.

Inbox The file into which incoming mail is delivered
Input Information entered into a computer, or the act of entering such information. You can input information using input devices such as the keyboard, mouse or a scanner.
Interface A term most often used to describe the ‘user interface’, which is the way a computer system or program is designed to work with its human operator.
Internet A global network of computer networks, allowing communication and information exchange.
Internet address See URL.

IP   Internet Protocol, used by almost all communicating computer systems, usually in combination with TCP (Transmission Control Protocol) to give TCP/IP

IP address The means used to identify the connection of a system to the Internet, conventionally represented by a four-component number (for instance, 131.111.8.42 which identifies a Computing Service DNS server). 
ISP Internet Service Provider.  ISPs maintain a dedicated communication line to the Internet; users dial in to the ISP, which then connects them to the Internet via a (hopefully) high-speed dedicated communications line.

J

Jazz Drive The Jazz disk, made by the same company (Iomega), stores even more information than a Zip disk.

JPG or JPEG Pronounced jay-peg. A graphics file format which can compress graphics to a fraction of their size. JPG uses ‘lossy compression’, which means that the higher the degree of compression, the more detail is lost from the image. JPG images are frequently used on Web pages because their small size reduces download time, and they have the file extension .jpg (or, occasionally, .jpeg).

K

KB See kilobyte.
Kbps Kilobits per second. A measure of data transfer speed. One kilobit is 1000 bits. A 56Kbps modem (ideally) transfers information at 56,000 bits per second. If you divide the Kbps rate by 10, you’ll get the approximate number of characters transferred in one second.
Kilobyte A measurement of memory. One kilobyte holds 1024 bytes.

L

LAN Local Area Network. A group of computers connected together within a fairly small geographical space, usually within one building.
Link A dynamic reference to another document (or another part of the current document).  Clicking a link will connect you to the destination document.
Linux An operating system which runs on a variety of computer hardware, including PCs. Linux has a very strong following due to its efficient design and because it’s offered free of charge under a system called open source. However, despite attempts to make a user friendly version of Linux, it is far more difficult to use than either Windows or Mac OS and is not suitable for beginners.
Log off, log out See sign off.
Log on See sign on.

M

MB See megabyte.
Mac OS An operating system designed by Apple which is used on Macintosh computers.

Malware A catch-all phrase used to describe Viruses, Trojans, Spyware and other types of malicious software.

Mailbox A collection of mail messages stored together (folder)

Mbps Megabits per second – millions of bits per second. A measure of data transfer speed.

Megabyte A measure of computer storage. All information in your computer is measured in bytes, with one byte containing the equivalent of a single character, such as a letter of the alphabet, a number, a punctuation mark (including spaces) and so on. A kilobyte is 2^10 bytes – 1024 bytes, although hard drive manufacturers often define it as 1000 bytes. A megabyte is 2^20 bytes – 1,048,576 bytes. These days, hard disk sizes are usually measure in gigabytes, 2^30 bytes – 1,073,741,824 bytes.

Megahertz A measure of frequency. Used to measure microprocessor speed.
Memory Random Access Memory (RAM). Temporary storage area for programs and data while your computer is switched on. Anything stored in RAM is lost when the power is turned off. Don’t confuse memory with storage.

Menu A list of options from which you can choose. You open a menu by clicking its title with the mouse; then you select an option by moving the mouse pointer to the desired option and then clicking.
MHz See megahertz.
Microcomputer A computer built around a single microprocessor, such as a PC or a Mac. These days the definition is getting a little stretched as microcomputers are sometimes built with two or more microprocessors working together.

Microprocessor A silicon chip that contains a central processing unit. The term is often used interchangeably with the term central processing unit when talking about personal computers.
Microfilter.  This device plugs into your BT phone socket and splits the line into a standard phone and a broadband line.  You will need one of these on every one of you sockets that you use in the house.  They are usually supplied when you sigh up to a telephone broadband service, like BT, Orange Broadband, but not Virgin media as this use fibre optics.

Modem Modulator-demodulator. A device used to transmit digital data (from your computer) across analogue phone lines.
Motherboard Sometimes called a main board. The main circuit board in a computer, holding the primary components such as the CPU and RAM.
Mouse A pointing device which lets a user interact with a computer.
MP3 A compressed audio format that has gained huge popularity. Thousands of musical tracks are available in MP3 format on the Web, and you can download these tracks using a browser or other software and listen to them on your computer or a portable MP3 player.
Multimedia The use of sound, video and/or animation as well as static graphics and text.
Multi-tasking A system which can perform more than one task at a time. Both Windows and Mac OS are multitasking operating systems.

N

Nanosecond One billionth of a second.
Netiquette Etiquette guidelines for behaviour on the Internet, in particular with regard to posting messages to newsgroups and e-mail.
Network Two or more computers linked together.
Newsgroup An online discussion group on a particular topic.
Newsreader An application that lets you read and reply to messages posted on Internet newsgroups.

O

Offline Disconnected from a computer communications system.
Online Connected to a computer communications system.
Open Also called run, load, start or execute. Opening an item (such as a program) activates it.
OS See operating system.

Operating System A collection of programs which, together, manage all the basic functions of a computer. The operating system runs other programs (such as a word processor or graphics editor), manages the storage of your own documents, and coordinates the functions of the computer itself and all the devices connected to the computer. Windows XP, Mac OS and Linux are three examples of operating systems. A program written to work under one operating system will not work on another operating system (a different version must be written for each operating system – such as Microsoft Office for Windows and Office for the Mac.)

Outlook A Windows application which can be used for email amongst other things

Outlook Express A Mail User Agent available on Windows; not supported on the PWF

Output Information processed by a computer program and displayed or stored on a device. Output may be printed, displayed on the screen, sent across a communications link, played through the speakers, and so on.

P

P2P See Peer to Peer

Parallel Port See port.
PC Personal Computer.  Usually used to refer to any computer that runs the Windows operating system.

PDF Portable Document Format: a format widely used for publishing on the Web, and read using Acrobat Reader 

Peer to Peer Software   A type of network in which each participating system has equivalent capabilities (unlike client-server architecture). Often used for file-sharing applications such as music sharing 

Pentium One of the microprocessor from Intel.
Peripheral Hardware component that you add to the central system unit of a computer, such as a monitor, printer, mouse.
Plug & Play The ability to configure a new device automatically.
Pop – Up A small windows that opens whenever you visit a web page.  Pop-ups are often used for legitimate advertising, but mostly are regarded as intrusive annoyances

Port A conduit for transferring information between a computer and an external device, such as a modem, mouse, joystick, digital camera or printer. Parallel ports (used by printers and scanners) transfer bits of information simultaneously in groups. Serial ports (used by modems and joysticks) transfer information one bit at a time. See also USB.
Post To place a message on a newsgroup or BBS.
Processor See microprocessor.
Protocol A set of rules which allows different parts of a computer network to ‘talk’ to one another.
Public-domain software  Any program that is not copyrighted, and is thus available for free use by anyone. (Note that ‘freeware’ is copyrighted software that is free.)

R

RAM Random Access Memory. The fast internal memory used by the computer to store information and instructions while the computer is operating. Anything stored in RAM is lost when the power is switched off.
Resolution The clarity of the image on the screen.
ROM Read-Only Memory.  Internal memory which contains permanent instructions.

Router.  This allows multiple PC’s to access a single broadband internet connection.  It usually automatically chooses the best route for the data your computer is sending or receiving

RTF   Rich Text Format: a standard for specifying formatting of documents. Many applications can save and read files as RTF, so it is useful for exchanging between applications. 

S

Scroll To move a document in a window so you can see any portion of it. You can scroll up and down or side to side using scrollbars to the right and bottom of the window.
SCSI (pronounced skuzzy) Small Computer System Interface.  A high performance design for connecting disk drives, scanners and other devices to a computer.
Search engine A program that searches pages on the Internet for specified keywords and returns a list of the documents containing the keywords. Examples include Google and AltaVista.
Serial port See port.

Server A computer or program that provides a service used by, typically, multiple clients: for example, a web server or mail server

Service Pack   A bundle of software updates from a supplier such as Microsoft (security patches, operating system updates, etc.)

Setup To install and configure computer hardware or software.  Most computer applications come with a setup program which steps you through this process.
Shareware Software which you can try out without payment. If you continue to use the software, you are honor-bound to pay the author the requested fee.
Shortcut A pointer to a file. Creating a shortcut allows you to quickly access a program or document no matter where it’s actually stored. The Mac equivalent is called an alias.
Sign off; sign out To finish a session on a computer system or network.
Sign on To start a session on a computer session or network. By signing on, usually by entering a username and a password, you let the system know you are connected.

Software A term for computer programs. A program is a series of instructions used to manipulate data or to control the workings of a computer system. The former type is often called applications software, while the latter is called operating systems software.  A word processor is an example of applications software; Windows XP is an example of an operating system.
Spam Electronic junk mail.

Spyware Software that sends and collects information, such as websites you have visited or credit card details, without your consent.  This can be used for identity theft.

Storage Any medium or device (such as a hard disk) used to store data for an extended period.
Surf To move from place to place on the Internet, usually using a Web browser.

T

Taskbar The long horizontal bar at the bottom of the Windows Desktop which you use to access programs and manage your Desktop.

TCP/IP Transmission Control Protocol/Internet Protocol, used by almost all communicating computer systems.
Toolbar Icons grouped together within a program, usually in a strip across the top of the window. Each toolbar icon or ‘button’ provides a shortcut to one of the program’s commands or features.
Tooltip  A short, informative message which pops up when you let the mouse pointer linger on an icon, menu option or other part of the user interface.
Traffic The amount of information being handled by a communications system. During times of heavy traffic on the Internet, you’ll notice your connections will slow.

Trojan Named after the infamous Trojan horse, this is a type of computer virus that works by disguising itself as helpful software, while spreading and attacking your PC

U

Undo To reverse your last action in a computer program. Many programs allow multiple ‘undos’ so you can reverse a whole series of actions.
Unzip To decompress a file that has been compressed using a program such as WinZip.
Upload To send information from your computer to a remote computer.
URL Uniform Resource Locator, the address used to identify documents and other resources on the Internet.  URLs consist of two parts, the first denoting which protocol to use to transfer the document and the second specifying the location of the resource. For example, addresses beginning with http:// use the Hypertext Transfer Protocol for transmission – the protocol for the World Wide Web. Addresses beginning with ftp: // use the File Transfer Protocol for transmission.
USB Universal Serial Bus. A fairly recent type of connector that is intended to replace serial ports. With USB, you can connect up to 127 different devices to your computer.
User friendly Easy to learn and use.

V

Video Conference A conference or discussion held via an audiovisual link between two or more geographically remote sites.

Virtual Not real. Something which is virtual has no physical basis itself but mimics a physical object in conceptual terms. For instance, on the Web you’ll find graphical representations of buildings which you can ‘walk through’ using your mouse. Such a building is a virtual building and it may be part of a larger virtual world.
Virus A computer program designed to replicate itself. Many computer viruses are innocuous; some are harmful and can either damage information and programs on your computer or cause your computer to malfunction.

W

Web Short for World Wide Web.
Web browser A software application used to locate and display Web pages.
Webcam A web camera (or webcam) is a real-time camera (usually, though not always, a video camera) whose images can be accessed using the World Wide Web, instant messaging, or a PC video calling application. The term webcam is also used to describe the low-resolution digital video cameras designed for such purposes, but which can also be used to record in a non-real-time fashion

Web page A document on the World Wide Web.

Webmail   A system for access to email via a web browser. In Cambridge, the term usually refers to the locally-developed Hermes Webmail facility.
Web server A computer that stores Web pages and delivers them to Web browsers on request.
Web site A location on the World Wide Web, consisting of at least one page (the home page) and possibly many pages.

Wi-Fi short for Wireless Fidelity or wireless connectivity.  It uses radio waves to link computers and other electronic equipment.

Wi-Fi card. You may need this to make your laptop, printer, PC or other device capable of communicating wirelessly.  It can be an Airport Card for Mac, a USB device for desktop PC’s or a PC card for laptops.
Window A portion of the screen used to display a program, document or data.

Windows An operating system designed by Microsoft. Most home users use Windows XP or the earlier Windows 2000 or the brand new Windows Vista. Most business users use Windows NT or Windows 2000.

Wintel A computer that contains an Intel (or compatible) microprocessor and which runs Microsoft Windows. That’s almost 90 percent of the personal computers in the world.
WLAN Wireless Local Area Network: a facility for connecting to a wider network using wireless technology to reach a local Access Point 

World Wide Web A collection of online documents stored on interlinked computers, called Internet servers, around the globe. The documents are written in a language called HTML that supports links to other documents. Users can view the documents using a Web browser, and can jump from document to document by clicking on the links contained in the documents. The Web is only a part of the Internet – some Internet servers perform functions other than being Web servers. For example, mail servers store and handle e-mail; news servers store and handle newsgroups.

Worms Like viruses, except that rather attaching itself to files or applications, worms run on its own.  They often use networks, enabling them to spread more rapidly over the internet.

Z

Zip To compress a file using a program such as WinZip. You zip files to package numerous related files together and to make them smaller, so they are easier to store on disk or to send to another user via the Internet. 

Zip disk or Zip Drive A portable device for storing information. Zip disks are about the same size as floppy disks, but they hold between 100 and 250 megabytes of information (compare that with the floppy disk’s 1.44 megabyte capacity). You need a Zip drive to read a Zip disk and, as with floppies, you can remove the disks and insert new ones when needed.

ZoneAlarm A firewall for protecting computer systems connected to the Internet