Uniquely tracking you based on your browsing environment

Whether you realize it or not, you can be uniquely identified by just visiting a website! When you visit a website, you carry a fingerprint that isn't necessarily unique, but unique enough. The EFF has released a tool called Panopticlick that uses various information that is provided by your browser.

For example, many people are familiar with the browser's user string; mine is "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:8.0.1) Gecko/20100101 Firefox/8.0.1". This isn't, however, the only information that gets passed along:



Based on this information, "Your browser fingerprint appears to be unique among the 1,881,909 tested so far.

Currently, we estimate that your browser has a fingerprint that conveys at least 20.84 bits of identifying information."

What does this mean for everyone else?