1.) Any program on your computer that reproduces its code
2.) Any program on your computer that completely fucks it up and disables its ability to work properly
3.) A said program that you probably got when you opened an
e-mail you didn't know
who it was from or
downloaded something that you didn't know what it was
4.) Windows
Person 1: My computer keeps
crashing, I think it has a virus.
Person 2: Did you open any emails you recieved from a stranger?
1: No.
2: Did you
download any strange
files?
1: No.
2: Are you running Windows?
1: Yes.