1.) A self-executable program designed to infiltrate and destory computer files and hardware.
2.) A virus must be able to replicate itself, and execute itself.
3.) file infector viruses, boot sector viruses, master boot record viruses, multi-partite viruses, macro viruses
4.) A trojan horse is a virus or undesirable program disguised as something else, such as pop-up games.
5.) programs that can replicate themselves without the use of a host file.
6.) hardware programs, virus protector detection, virus-like activity detection, certain documents will not open, computer does not register 640 K of conventional memory.