human
What are the different types of computer viruses and how do they work?
assistant
1.  The most common type of virus is a Trojan horse, which is a program that appears to be harmless but actually contains malicious code.
2.  A worm is another type of virus that replicates itself by sending copies of itself to other computers over the internet.
3.  Adware is a type of malware that displays advertisements on your computer screen.
4.  A rootkit is a type of malware that allows an attacker to gain control of your system’s kernel, giving them complete control over it.