Computer Virus

A computer virus attaches itself to legitimate files or programs and copies itself whenever those files are opened, spreading from file to file and sometimes from device to device. Depending on how it's written, the damage ranges from harmlessly displaying messages to deleting data. Colloquially "virus" is used for any malware ✕ Malware (from "malicious software") is the umbrella term for any harmful software — viruses, trojans, ransomware, spyware — that damages, spies on, or hijacks devices. More in the glossary → , but technically it's just one subtype. You're protected by an antivirus ✕ An antivirus is a program that detects, blocks and removes malicious software. Modern ones combine known signatures with behavior analysis. More in the glossary → program that detects viruses through known signatures and suspicious behavior. More in the best antivirus comparison.