Antivirus software
Antivirus software is available as free or commercial products. Both will perform these functions:
- scan the hard disk, SSD and memory sticks for existing malware
- scan emails for malware
- scan downloads for malware
- quarantine malware files so they can not be run
- attempt to repair infected files
- provide an update mechanism to get the latest virus definitions
It is important to allow antivirus software get updates to the latest virus definitions - preferably daily. If there is option to turn this on or off, make sure it is on.