How are virus developed?

Bug are produced by individuals who wish to cause harm to others, or who wish to acquire control over somebody else's computer system. The easiest way to produce a virus is to take some existing code and modify it slightly.  https://sakeradvantage.com/?p=987 This new code can then be dispersed to others, who might unknowingly run it by themselves computers. As soon as the virus is running, it can do anything its creator desires it to, including deleting files, stealing data, or sending spam. More advanced infections can be really tough to eliminate and detect.