|MadSci Network: Computer Science|
The short answer to your question is: it depends on the game, the server, and your anti-virus software.
Many online games are now written in Java. Now Java has a number of built-in security features to prevent applets from having an adverse effect on your computer. For instance, applets are not supposed to be able to perform file operations on a remote computer (i.e. write, read, or delete your files). Also, often your browser will have security features that may help catch security violations from a remote applet, but I wouldn't put too much faith in that safeguard.
Now, if the game is not written in Java, the security falls to the browser, which is easier to circumvent than the Java security. Lastly, we come to online games which you download programs to run (i.e. You Don't Know Jack: The Netshow, Acrophobia). These are, by nature, rather insecure. After all, it installs files to your hard drive, manipulates your registry, and controls your connection.
Don't get me wrong, if it's a company you can trust, like Bezerk, I'm sure there's no problem. I've run both of these programs and never experienced any problems. I'm just using them as an example of the games where you have to download and install something to play it online. Be sure you can trust whomever you download these files from.
So, basically, if the game's in Java, I wouldn't worry about it. It's very difficult (although possible) to circumvent the security features. If it's something else, but still wholely contained on the remote server, you're relying on the security features of your browser, which, if you're using Netscape aren't too bad. Of course, they can be beat too. If you have to download something to play the game, be very careful and be sure you trust the company.
As for your anti-virus software, well, it would probably only detect a virus in the second case (non-Java, server-based game). Personally, I don't put a lot of trust in the Internet-based anti-virus software. But, it certainly couldn't hurt to have one running.
I hope this answers your question. If you have any further questions, please feel free to E-mail me at email@example.com.
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