how to prevent these windows within web pages

["H.S." <hs.samix@gmail.com>]

If I go to this web page, I get a window within the web page and I have 
to click on "close window" to get rid of it:
http://linux.sys-con.com/read/32640.htm

How are these kind of windows implemented? Java script? And how do I 
prevent these kind of windows on Mozilla and Firefox? I don't get any 
other kind of popups or extra windows, but these kind of windows seem to 
be circumventing the blockers.

thanks,
->HS