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I was getting interested in data privacy and looked up how users are tracked on the internet to connect the different traces to a single user. I found this:
In addition to regular cookies, pixel tags, ultrasound beacons and fingerprinting technologies, there exists other methods for tracking users, such as undeletable zombie cookies or super cookies, dynamic cookies, Silverlight Isolated Storage, IndexedDB, etc. (source)
I wonder what other methods the "etc." entails?