The term that describes a virus that spreads without user intervention is known as a worm. Unlike traditional viruses, which require host files to execute and propagate, worms can replicate themselves across networks and systems automatically. This self-replicating behavior can lead to rapid dissemination and significant damage, often causing network congestion and security vulnerabilities. Worms exploit software flaws or vulnerabilities to infiltrate systems, necessitating strong cybersecurity measures to prevent their spread and mitigate their impact.