How do computer worms differ from computer viruses?

While both computer viruses and computer worms are forms of malware used in cybercrime, they differ fundamentally in how they operate and propagate:

• Dependency on a Host: A computer virus is a portion of code that must attach itself to another program or file to function. It "infects" these host programs, which continue to perform their intended tasks while surreptitiously executing the virus's instructions. In contrast, a computer worm is a complete, independent program that does not require a host to function.123
• Replication and Propagation: Viruses typically spread by instructing their host program to copy the viral code into other files or programs on a computer, often requiring human action to transfer between systems via storage devices or networks. Worms are designed to replicate and propagate automatically across telecommunications networks without needing human intervention.123

Both threats can cause significant damage, including data theft, system crashes, or denial-of-service attacks, and both are subject to legal scrutiny under laws such as the Computer Fraud and Abuse Act.24