At a crime scene, detectives are able to lift fingerprints that are not visible to the naked eye. But those fingerprints tell a lot about who was at the scene.
It's a very similar situation when you visit a website. You can't see it, but your web browser may leave unique fingerprints everywhere you go, revealing who you are and what you're doing.
Security experts warn that these fingerprints can be monitored, tracked, and identified by companies that want to sell you something and hackers who want to steal from you.
"Fingerprinting on computers is invisible to most people but there are companies out there who are already using these techniques to learn more information about individuals, about their interests and their habits," said Lachlan Kang, an Australian computer science doctoral student at the University of Adelaide.
So what, you ask? Kang answers that in its most benign form, it might mean you get a barrage of ads, based on the sites you visit.
You might already have noticed that. If you search for a particular item on Amazon.com, for example, you may see adds for that item pop up on every website you visit after that.
At worst, though, Kang says this cyber sleuthing could be used to spy on you.
"Computer users generally are growing in awareness of privacy issues, but currently there's little that can be done to counter fingerprinting,” Kang said. “This is because fingerprints build up in between the websites you're visiting – your browsing history and personal information can be pooled in the gaps between those websites. Simply clearing your browsing history won't make any difference to this, because the information is already out there."
Working on a defense
Kang's goal is to build a defense against third parties that are following your fingerprint trail. He hopes to develop a software that acts in a similar way to anti-virus, allowing users who have installed it to block outsiders from seeing their browser fingerprints without their consent.
Kang is currently enlisting volunteers who would agree to allow him to analyze their digital fingerprints. He says he has about 25% of the number he needs.
In the meantime, if you'd like to get more information, or view your own browserprint, check this out.