Computer viruses are malicious programs that are designed to damage your computer or compromise your security. Before using the internet, it's important to make sure that your computer is protected by antivirus software. Without it, it's quite easy to download a virus unintentionally.
Antivirus software will protect your computer by preventing an attack by or detecting and removing any viruses. Some antivirus software can be downloaded for free from the internet – for instance, AVG and Windows Internet Security. Other types, such as Norton or McAfee antivirus software, have to be paid for with an annual subscription.
All antivirus programs have to be regularly updated, as new viruses appear on the scene.
Some antivirus also protects against spyware – software that collects information about the user, such as which websites they've visited.