What's a botnet?

Excerpts:

Thousands or even millions of PCs are being hijacked by malicious programs to commit Internet crimes.

Serry Winkler, a sales representative in Denver, said that she had turned off the network-security software provided by her Internet service provider because it slowed performance to a crawl on her PC, which was running Windows 98. A few months ago four sheriff’s deputies pounded on her apartment door to confiscate the PC, which they said was being used to order goods from Sears with a stolen credit card. The computer, it turned out, had been commandeered by an intruder who was using it remotely.

So far botnets have predominantly infected Windows-based computers, although there have been scattered reports of botnet-related attacks on computers running the Linux and Macintosh operating systems. The programs are often created by small groups of code writers in Eastern Europe and elsewhere and distributed in a variety of ways, including e-mail attachments and downloads by users who do not know they are getting something malicious. They can even be present in pirated software sold on online auction sites. Once installed on Internet-connected PCs, they can be controlled using a widely available communications system called Internet Relay Chat, or I.R.C.

Attack of the Zombie Computers Is Growing Threat

What can one do?

1. Have latest patches installed for your system(s).
   
2. Have a good Internet security product (Symantec or McAfee)
   
3. Upgrade to Apple OS X or Linux. Windows XP2 SP2 is a good operating system and Vista probably will be as well.