In computer system security, an infection is a type of destructive code or program that self-replicates by placing its code into other programs. As an outcome, contaminated computers can spread out the virus to other computers. Viruses are frequently spread out by e-mail accessories, social networks links, and online ads. The most common type of bug is theTrojan horse, which tricks users into clicking on a destructive link or e-mail accessory. article source