A program from Adobe System that saves files in portable document format (.pdf). These .pdf files can be viewed by anyone who has the Adobe Reader, a small, freely available program (you can download it from http://www.adobe.com).

Any software used to carry out everyday productivity tasks; word processors, databases and spreadsheets are all examples of applications software.

Short for American Standard Code for Information Exchange, a long-established way of representing English characters and keyboard symbols by giving each one a number from 0-127. Most word processors can save text as an ASCII (or 'plain text') file that can usually be read by a different word processor, even on a completely different type of computer.

The process of copying computer files or data from one storage medium (eg a hard disk) to another, such as a ZIP disk, as a safeguard against loss of the original data.

A type of computer graphic image built up with rows and columns of dots. The sharpness of the image depends on the density of the dots - its 'resolution'.

The type of software used to find and display Web pages. The two most popular browsers are Mozilla and Microsoft Internet Explorer.

A collection of wires through which data is sent from one part of a computer to another. In fact, a PC has two buses. The internal bus connects the computer's own components to the CPU and the memory. The external bus allows expansion cards (often used for better sound or graphics) to connect to the CPU and memory.

a unit of computer data storage. Each byte consists of eight bits.

a kind of high-speed storage mechanism that allows the PC to access frequently used data at a much higher rate than from conventional RAM.

Stands for Compact Disk Read-Only Memory, a removable computer storage disk capable of holding up to 700 Mb.

A small message sent from a Web site to the browser on your PC and stored there in a file called cookie.txt. Cookies are most often sent your PC so that the site can instantly identify you when you revisit it and prepare customised pages for you.

Short for Central Processing Unit, the microprocessor, or chip, at the heart of your PC. It is where most of the PC's calculations take place, and is the single most important component in determining the speed of your system.

To transfer data from a main device to a secondary one. The term is most often used for copying files and programs from the Internet to your PC; in such a case you are said to download the data from the Web server on to the 'local' hard disk in your PC. The reverse of this process, for instance, when you add new data to a Web site, is known as uploading.

The dominant technology in local area networking (LAN) since its development in the mid-1970s. To connect to an Ethernet network, you need to add a special Ethernet card to your PC.

File Transfer Protocol, the system used for sending files on the Internet. In order to update your own Web site, you will need an FTP program to upload the files.

Short for gigabyte. One Gb equals 1024 megabytes (Mb). the storage of PC hard disks is measured in Gb.