There are three ways through which viruses can get into your computers.
A very common way of entrance for viruses is CD/DVD or U.S.B. Drives. Have you noticed that when you insert original software disks or Windows installation disks into your CD drive, installation of that software starts automatically? There is one file inside your Disk or U.S.B. Drive called "Auto run.inf", this file tells the system to start some application or to execute some commands automatically when the disk is inserted.
When you burn CD/DVD Disk or insert U.S.B. Drive in an infected computer, viruses (running in background process and observing your computer) put a copy of itself and auto-run.inf file into that disk or drive. If you insert such infected drives/disks into a fresh healthy system, that system will also become infected. In this way viruses travels from infected computers to healthy computers through CD/DVD or U.S.B. Drives.
Viruses can also spread through LAN (Local Area Network). If an infected system is attached to a healthy network or one of the computers of a healthy network gets infected, viruses will spread through out the network.
If you download software from not trusted websites, remember that "Nothing is Free" and "If you are getting it free, you might be sacrificing your privacy or your system behind the scene".
Such pirated software comes with cracks like crack.exec, patch.exec, key gen.exec etc. And with my personal experience I found that most of those crack contains virus infection in it, in some case software itself comes with virus infections from such a site.
So keep aware and be safe on-line. Enjoy a virus free computer world.
Visit http://www.basicknowledge.co.in for more basic knowledge on computers and your online security.
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