How Digital Fingerprinting Works

Digital Fingerprinting and Your Identity

Every time you surf online, you're leaving invisible fingerprints all over the Web.
Every time you surf online, you're leaving invisible fingerprints all over the Web.

The last page delved into the technology powering digital fingerprinting as we typically think of it, but the term sometimes refers to an altogether different form of data tracking. This can be pretty confusing. We all know what fingerprinting normally means (we only have one set of fingerprints!), but entering the digital world opens up room for ambiguity. In recent years, digital fingerprinting has been used to describe a method of identity tracking -- essentially, every computer has a unique fingerprint that makes it trackable across the Internet.

You've probably heard of IP addresses, the unique numbers attached to every computer on the Internet. An IP address isn't an exact identity card for a computer. Real fingerprints never change, but Internet service providers (ISPs) can change users' IP addresses. Digital fingerprinting accounts for other details to pin down the identity of your computer. And here's where things get a little scary: It's shockingly easy for Web sites to read various bits of data about your computer and figure out who you are. The IP address is just the first step -- this shows who your ISP is and what country you live in. The login identity you choose on a Web site can be another clue. If you use the same login on multiple sites, that name may be easy to track down with a simple Google search. The operating system installed on your computer, be it Windows or Mac OS X or Linux, tightens the focus. Even the web browser you use (and the specific version you're running, like Google Chrome 11.0.696.60 or Firefox 3.6.17) adds detail to your digital fingerprint [source: Wall Street Journal].

As you can see, the technology exists to track your activities on the Internet. But is this really a bad thing? Well, that depends on how much you value your privacy. One use of this technology lies in targeted advertising, which would take your data into account to provide ads more likely to appeal to your interests. If you've ever noticed Google Ads grabbing keywords off a page you're viewing to provide more topical ads or been surprised when Web sites mysteriously identify the city you live in, you've seen a basic version of this technology at work. As this kind of tracking becomes more common, advertising and tracking companies will supposedly offer opt-out Web sites (much like telemarketer "do not call" lists) that will protect your anonymity. Still, you should always be aware of how easily your identity can be traced.