Do you believe that you are anonymous when you surf the web? Your computer may reveal more information than you thought - possibly enough to identify your computer uniquely.

Computer experts refer to the idea of a "device fingerprint," which is a summary of the hardware and software settings that can be collected from your computer by web sites that you visit.

Thanks to the Electronic Frontier Foundation (EFF), you can now see what web sites can see when they look at your computer.

Panopticlick is a unique website that pulls the information (that you didn't know you had) about your computer that all websites can see, and then display it for you. Panopticlick tells you how unique your computer is, based on its configuration, which provides the equivalent of a device fingerprint.

According to the EFF:

"When you visit a website, you are allowing that site to access a lot of information about your computer's configuration. Combined, this information can create a kind of fingerprint - a signature that could be used to identify you and your computer. Some companies are already using technology to try to identify individual computers. But how effective would this kind of online tracking be?
"EFF is running an experiment to find out. Panopticlick will anonymously log the configuration and version information from your operating system, your browser, and your plug-ins, and compare it to our database of many other Internet users' configurations. Then, it will give you a uniqueness score - letting you see how easily identifiable you might be as you surf the web."
It turns out that science fiction writer Philip K. Dick gave us all a heads-up on this situation more than forty-five years ago. In his 1964 book The Penultimate Truth, he wrote about what he called an "ident-key" which not only identified the person, but every bit of intellectual source material that person had ever accessed:
"'Your ident-key, please,' the ruling monad of the archives buzzed. He slid his key into the slot; it registered, and now the ruling monad, after consulting its memory bank, knew and remembered every source item he had ever utilised, and in what sequence; it comprehended the entire pattern of his formal knowledge.

"From the archives' standpoint, it now knew him without limit, and so it could declare - or so he hoped - the next point on the graph of his growing, organic, mentation-life. The historic development of him as a knowing entity." (Read more about Philip K. Dick's ident-key)
Also, for those who enjoy word origins, "panopticlick" appears to be the mating of the word "Panopticon" and the phrase "mouse click". A Panopticon is a circular prison designed by English philosopher Jeremy Bentham in 1785; the idea is that all prisoners could be observed at all times in their cells from a central guard office by means of simple optics available at the time.

You can see your computer's fingerprint at the Panopticlick website