A Trojan horse is a type of malware that disguises itself as a legitimate program or file to trick users into downloading or executing it. Unlike viruses or worms, Trojans do not replicate themselves; instead, they rely on users to unknowingly install them. Once activated, they can perform various malicious actions, such as stealing personal information or granting unauthorized access to the user's system. Trojans can be delivered through various means, including email attachments, software downloads, or compromised websites. Users are often lured by enticing offers or fake updates, making it crucial to maintain good cybersecurity practices, such as using antivirus software and being cautious with unknown sources.