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Fresh from penning our Firewall and Virus Alert   article, PCSTATS would like to present the second part of our beginners guide to the less savoury aspects of the internet experience; dealing with the subject  of "Spyware." If you've installed a peer-to-peer sharing program such as 'Kazaa Media Desktop' or 'Morpheus', or accidentally said yes to a 'Gator' pop-up, or gone on an excursion to some of the darker corners of the Internet, chances are your PC has developed an internet life of its own through one or more spyware applications.  
What is Spyware?
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   While the actual definition 
of what constitutes                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               Spyware is somewhat vague, there are a few distinguishing points that are generally agreed on. The most common definition of Spyware is a program that sends information from your computer to another destination on the Internet without your knowledge  and without your explicit consent. The information can potentially include just about anything stored on, or accessible by your computer. In reality, most spyware programs limit themselves to sending specific types of demographic information, such as the URLs you visit on the Internet, IP and email addresses, or even something as mundane as a cookie.
The potential of these kinds of programs is rather frightening though. On a 
modern Windows XP based computer, any program installed by a system 
administrator (that is, any of the users created during the install process, as 
well as the built in administrator account) has access to all files on the 
system. This allows all sorts of mischief to be committed with your implied 
permission. 
   Permission really is at the heart of the issue when it 
comes to spyware, since to separate themselves from the makers of viruses 
and 'trojan horse' programs, creators of spyware need your okay to install their 
products on your system. Of course, standard operating procedure is to make 
this request as obscure as possible, so as to insure a large installed base of 
users. 
  Some software uses a cerificate window request to attempt to 
gain your permission, as seen most famously with the Gator Corporation, whose 
ubiquitous ads are launched by any number of sponsored web-sites and software 
installation packages. If you click "ok" to the request, the Gator software 
will be installed on your computer. 
Others, as is commonly seen with spyware packages included along with common file 
sharing applications like Kazaa Media Desktop, use passages in the End User 
Licensing Agreement (EULA) to gain your acceptance. 
   Since these legal agreements are rarely read by computer users 
and can be torturously worded, they are an easy vector for spyware to be 
installed as a component of a popular freeware programs. 
Once installed, spyware software can easily send any required information out 
to the Internet using the system's current connection. Such transactions occur 
in the background and are difficult to notice or trace, since most firewall 
hardware and software, including Windows XP's built in firewall, does not 
interfere with information going out of the protected computer or network.