Although viruses and spyware are often grouped together as malware, they are different. The effects of a virus infection range from annoying messages to an unusable computer, but spyware is designed to spy on the computer's users. This could involve monitoring websites visited or recording credit card numbers as that can spot dubious emails, and the latest versions of Firefox and Internet Explorer alert users to known phishing sites.

To ensure that Internet Explorer's phishing filter is enabled, click on the Tools button, then Phishing Filter, followed by Phishing Filter Settings. Scroll down to the bottom of the list of options and make sure that 'Turn on automatic website checking' is selected.

The best protection against phishing is caution. Even if you think an email from a bank or shop is legitimate, don't click on links it contains, as these may take you to a counterfeit website.

Open your web browser and go to the site by typing its address into the address bar. Never respond to an email that asks you to 'confirm' an account username or password.