Unfortunately, many existing mechanisms to gauge and propagate trustworthiness—to work out if an interaction with a site is from a real human, for example—take advantage of techniques that can also be used for fingerprinting.

The mix of a fingerprint and first-party cookies is pervasive as Google can give a very high level of entropy when it comes to distinguishing an individual person.

Browser fingerprinting is a powerful method that websites use to collect information about your browser type and version, as well as your operating system, active plugins, timezone, language, screen resolution and various other active settings.

Browser fingerprinting is defined on Wikipedia as follows: “A device fingerprint, machine fingerprint or browser fingerprint is information collected about a remote computing device for the purpose of identification. Fingerprints can be used to fully or partially identify individual users or devices even when cookies are turned off.”

Browser fingerprinting is quite a powerful method of tracking users around the Internet. There are some defensive measures that can be taken with existing browsers, but none of them are ideal. In practice, the most realistic protection is using the Tor Browser, which has put a lot of effort into reducing browser fingerprintability. For day-to-day use, the best options are to run tools like Privacy Badger or Disconnect that will block some (but unfortunately not all) of the domains that try to perform fingerprinting, and/or to use a tool like NoScript for Firefox, which greatly reduces the amount of data available to fingerprinters.

Browser fingerprinting is both difficult to detect and and extremely difficult to thwart.

“Browser fingerprinting” is a method of tracking web browsers by the configuration and settings information they make visible to websites, rather than traditional tracking methods such as IP addresses and unique cookies.

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 use this technology to try to identify individual computers.