A virus is malicious software that attaches itself to legitimate files or programs and spreads when the infected file is executed. It can corrupt data, slow down systems, or damage files.
A worm is a standalone malware that spreads automatically across computers and networks without requiring user interaction. It can rapidly infect multiple devices and consume network resources.
A Trojan Horse is malware disguised as legitimate software. Once installed, it can steal sensitive information, provide unauthorized access to attackers, or install additional malicious programs.