A reputable antivirus program will safeguard you from all kinds of malware such as worms and Trojan horses. In addition it should be able to detect and stop the spread of potentially unwanted software (PUPs) which could modify your browser settings, or display ads on your screen. Some premium antiviruses provide additional features like dark web monitoring, ID theft alerts and parental controls.

If you’re running Windows Microsoft’s built-in security against malware, referred to as Windows Defender on older computers or Windows Security on more recent machines, does an adequate job in keeping your computer safe. It’s not as effective or efficient in detecting malware like standalone antivirus brands that frequently score well in independent lab testing. It also doesn’t offer any additional security tools, such as a password manager or software for other devices.

The best antivirus for Windows that is based on malware protection, system impact, and user-friendliness it is Bitdefender Antivirus Free Edition. It scores high in the respected AV-Test labs and is easy to install and run. It offers protection for one PC for a minimal cost, however for a few dollars you can upgrade to more comprehensive protection with Bitdefender Total Security and Antivirus Plus.

A quality paid antivirus program will usually come with a number of additional features. They could include the use of a VPN, performance-optimization tools, and software for Mac OS, iOS, and Android. However, if you’d rather just stick with the basics, Sophos Home Premium offers powerful malware protection and additional features for an affordable price.