# The 'Fingerprinting' Tracking Tool That's Virtually Impossible to Block



## TechSocial (Dec 20, 2011)

The 'Fingerprinting' Tracking Tool That's Virtually Impossible to Block

A new, extremely persistent type of online tracking is shadowing visitors to thousands of top websites.

The type of tracking, called canvas fingerprinting, works by instructing the visitors web browser to draw a hidden image, and was first documented in a upcoming paper by researchers at Princeton University and KU Leuven University in Belgium. Because each computer draws the image slightly differently, the images can be used to assign each users device a number that uniquely identifies it.

Like other tracking tools, canvas fingerprints are used to build profiles of users based on the websites they visit  profiles that shape which ads, news articles or other types of content are displayed to them.

Read More


----------

