Ad companies love to track cookies on your computer to find out more about your online behavior, so they can send you targeted ads online. But, these companies could be turning to a new online tracking technology to replace those cookies that I've taught you how to block.
Canvas fingerprinting is a scary new way that companies can track your online behavior. It works by asking your Internet browser to draw a hidden picture. Almost every computer is different, so it draws the image slightly differently. This gives the company a unique way to identify your computer.
Device fingerprints rely on the fact that every computer is slightly different: Each contains different fonts, different software, different clock settings and other distinctive features. Computers automatically broadcast some of their attributes when they connect to another computer over the Internet.
The code most often found by researchers was created by a company called AddThis, and it's more common than you might think. They found the code on five percent of the top 100,000 websites. That's 5,000 sites! The code was present on everything from WhiteHouse.gov to seedy adult-entertainment sites.
This computer fingerprint tracking is hard to block because you can't use traditional methods I've told you about like your browser's security settings or ad blocking add-ons. AddThis says it won't use the data it collects for ad targeting or personalization if users opt out on their website. But, that's asking you to trust a company that's been secretly monitoring your Internet usage.
Tor, the Web browser that offers anonymity online, offers an added feature to its Web browser that will notify you when a website tries to use the fingerprinting code and will send back a blank picture. But, even Tor isn't always as secure as it seems.
This is some scary new technology, and you can be sure that I'll be keeping my eye on it to give you updates as I discover new ways to block it.