A type of unwanted program, which, if it manages to install itself on your computer, will attempt to show you pop-up advertisements, or redirect your Internet search to a different page, with links to websites it wants you to buy from. Adware is generally not really dangerous, but is fraudulent and can be very irritating.
Any type of computer file, such as a Word document, picture, video clip, or program file, sent with an email message. An attachment from a friend or family member is usually something nice, but attachments in spam emails can contain dangerous programs.
A program that protects your computer against viruses. These days, antivirus programs protect against all types of dangerous programs (malware), including worms, Trojans and spyware.
A program that protects your computer against spyware and adware. These days, standalone antispyware programs are not used so much, because antivirus programs now protect against all types of malware, including adware and spyware.
To copy any type of computer file (document, picture, video, music, program) from a website on the Internet to your own computer. It's possible to download good or bad things. Note that downloading a program file, such as Quick Time, is rather like buying a furniture as a flat-pack from IKEA and taking it home; before you can use it, you have to put it together in the right place; this second stage is called installing (see below).
A means of protecting your computer against anyone who tries to access it over the Internet. This can be a computer program, or a physical device.
Nearly all computer programs (good and bad) come in packaged form, rather like a flat-packed piece of furniture from IKEA. To use the program, it must be unpacked, and the components need to be put together in the right places, in the same way that a flat-pack must be unpacked and assembled to make a table. Installing a program usually means running a file called "setup" or "install".
Any type of dangerous program that could damage your computer, allow someone else to take control of it, or steal your personal data. Viruses, worms, Trojans, spyware and adware are all types of malware.
A phishing email is an attempt to defraud you by stealing your Internet banking details. It will claim to come from a bank, and will contain a link that supposedly goes to the bank's website, but actually leads to a fake site, which will steal your password etc if you enter them.
A rogue program is a dangerous program disguised as an antivirus or antispyware program. It is an example of a Trojan, a malicious program disguised as something good.
An unsolicited email sent to multiple email addresses. Spam emails are not necessarily harmful; some are just unwanted advertising, although many contain malicious attachments or links.
A type of dangerous program that attempts to steal your personal information, such as credit card details.
A dangerous program which is disguised as something desirable, such as a screensaver, video clip or music track.
A piece of harmful program code which embeds itself into a normal computer file such as a Word document or normal program. When the document is opened, or the program run, the virus is activated. It will carry out whatever malicious action is programmed, such as damaging your computer system, and attempt to infest any other vulnerable files it finds.
A dangerous program which can copy itself and spread from computer to computer over a network.