A bug is a piece of code that is developed to interfere with the normal functioning of a computer system. Infections can spread rapidly and trigger substantial damage to both specific computers and networks. Some infections are harmless, while others can delete files, corrupt information, or even damage hardware.
A trojan horse is a piece of code that is developed to disrupt the typical performance of a computer. Viruses can spread rapidly and trigger considerable damage to both specific computers and networks. Some viruses are safe, while others can delete files, corrupt information, and even damage hardware.