Although popularly grouped together as "virus",
there are actually clear distinctions between
different types of infection:
Term meant to indicate any kind of program with
malicious intent. Viruses are designed to multiply
and spread to other computers with human help
- such as when you open an email attachment.
They may or may not damage the infected computer.
A program capable of spreading by itself, without
human intervention. Worms may or may not have
a malicious "payload" that damages infected
Horse: Similar to the famous Greek myth,
a Trojan Horse is a malicious program hidden
inside another seemingly legitimate program
- such as a harmless game sent as an email