True, but if you start from scratch you should not ride the net bareback

http://www.cbc.ca/news/background/computer-security/
Twenty minutes. That's how quickly an unprotected computer can become infected on the internet, according to research institute Sans.org.

Ryan Purita, a consultant with Totally Connected Security Ltd., wanted to see this for himself. He hooked up a PC with default Windows settings to the internet: It had no anti-virus software, no firewall, and no operating system patches. In about one minute, says Purita, it was hacked, infected, and it had started propagating viruses to other computers. Purita recorded what happened in a video [RealVideo runs 2:00].
:develish: