A computer worm is a type of malicious software that replicates itself to spread to other computers. Unlike a computer virus, which attaches itself to files, a worm can operate independently and often exploits vulnerabilities in software or networks to propagate. Worms can cause significant damage by consuming bandwidth, deleting files, or installing other harmful software. They often spread through email attachments, downloads, or network connections, making them a common threat in cybersecurity. Protecting against worms typically involves using updated antivirus software and maintaining secure network practices.