Viruses are programs that disrupt the operation of computers by introducing changes in the operating system. These viruses come to computers via floppy disk, network, email, Internet, etc.. Enter and modify programs, thereby preventing them from fulfilling their duties. They are designed with the user can not detect them and to their reproduction. This spread is when the virus passes from one computer to another. The virus starts to act after the infected files or programs are executed. Until then, remain latent in the minds of the affected computer. Sometimes staying in hard disk sectors and are activated when you turn on your computer.
1. The creator of a computer virus in a file puts q is hidden in a program.
2. A user downloads, for example, the Internet, the virus program on your computer.
3. The user copies the infected program, and unwittingly delivers it to a third party.
4. The latter virus program loaded on the hard drive of your computer. Several programs are affected.
5. The second user gives another person, being used in college he attends, where many infected computers, and east to a room, that leads to employment, where the same phenomenon occurs in the university.
It was in 1985. That year went on sale in the United States two viruses. One of them was disguised in the form of a breeding program called EGATBR graphics. The second was a computer game called NUKE-LA.