Antivirus and Malware tools

For information about how to clean malware from your computer, or prevent it in the future, see this malware guide

Definitions

Term Definition
Malware Malicious software.
Virus A type of malware that spreads itself to infect more computers.
Trojan A type of malware that misleads users into thinking that it is a legitimate program. Named after the Greek Trojan horse.
Worm A type of malware that spreads itself. The difference between a worm and a virus is that a virus needs to be run on a host computer to spread, while a worm is independent.
Antivirus (AV) A program that runs constantly in the background, scanning files on download, on access, or on a schedule
Anti-malware (AM) A program that runs on demand to check for residual PUPs or other issues.
Potentially Unwanted Program (PUP) A generic term for an application that may not be malicious but is not wanted/intended regardless.

View more definitions here.

Windows Defender

The built in solution for AV in Windows 10 is more than adequate for consumers. This is much better than running a free AV suite that is of lesser quality or plans to sell your personal habits for profit (McAfee, Avast, AVG, etc)

Free Alternatives

All free alternatives are considered PUPs. They will sell you as their product and provide more a more troublesome experience. We do not recommend Avast, AVG, Kaspersky, McAfee or any other alternative AV.

We do not recommend any paid AV suite for consumers, they do not provide significant advantages over Windows Defender and only increase overhead.