- navigator - This will contain information about the browser vendor and version, plugins supported, MIME types and some information about the OS and architecture of the machine running the browser.
- screen - Information about the resolution of the monitor, and number of colours and pixel depth.
Firegloves was a proof of concept Firefox extension created for research purposes which tries to randomise the fingerprint. Acar et al. found that it was quite ineffective against preventing fingerprinting but since it is no longer maintained this could be because of changes to the Firefox extension system. Ironically since Firegloves itself is detectable this could actually become part of the data used to fingerprint a user due to its limited user base (1750 users).
"Do Not Track" (DNT) is an HTTP header field which allows users to request that websites do not perform any tracking and is implemented in many modern web browsers. Acar et al. ran their experiments again, this time with the DNT field set to 1, but found that this yielded exactly the same results. This shows that websites are simply ignoring user's tracking preferences.