It didn't have to happen. PC owners could have easily inoculated themselves against the bug with a little know-how. Toxic virtual vermin used to be rare, almost exotic. About the only means of passing viruses around was via floppy disks. But with e-mail and the Internet, computers are interconnected by the millions, greatly increasing the pathways for contagion.
Many users remain oblivious to the danger, and have done little to protect themselves.
They should do more. Know your enemy. A virus is a small software program that makes copies of itself and surreptitiously attaches them to other applications and files. Like their biological namesakes, computer viruses move about unseen, and can be passed to others unbeknownst to you when you share infected software and data. What the bug does once inside your PC depends on the fiendishness of its creator.