UNIX for Dummies Questions & Answers

Can anyone explain why generally there are no viruses in Unix.

Do any of the big Anti Virus supplier produce anything for Unix platforms ?

There are many unix exploits, worms, and other malware.
A lot of ISP's use unix systems, so unix vulnerabilities are well known to the hacker community.

In terms of malware, etc. that impacts widely, Windows wins. There are way more Windows boxes hitting the internet than anything else, so if you want to succeed with desktop malware, your preferred platform is Windows.