A bug is a type of harmful code or program that, when executed, replicates itself by customizing other computer programs and placing its own code. When this duplication succeeds, the impacted areas are then stated to be infected with a virus.
https://ivfsurvivalguide.com/?p=199 Viruses typically spread by developing a copy of themselves on a user's computer system without the user's knowledge or consent. Oftentimes, viruses will be spread by e-mail attachments or by files shared on peer-to-peer networks. Once a virus has actually contaminated a computer system, it can infect other computer systems on the same network.
Some viruses are set to spread themselves in such a way that could trigger major damage to a computer system. A virus may erase files, fill a hard drive with useless data, or corrupt system files. In some cases, an infection might even display a message or image that is designed to terrify the user.
Many viruses are fairly harmless, and just trigger small annoyance to the user. great post to read However, some infections can be extremely harmful, and can cause widespread damage to computer system systems.