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Basically, web browsers uses different image processing engines, export options, compression level, so each computer draws the image slightly differently, the images can be used to assign each user’s device a number (a fingerprint) that uniquely identifies it i.e. Browser fingerprinting. According to a research paper published by computer security experts from Princeton University and KU Leuven University in Belgium, the Canvas fingerprint tracking has made it more difficult for even the sophisticated computer users to protect their privacy.