How do websites know what device I'm logged in with?

I asked: how do Amazon and some of these banks know what device I'm logged in with? Is it strictly cookies? or MAC address, too? or...?

Sidd replied: heehee, are you running an app or your web browser ? windows or phone ?

There are a million ways, there is a GUID associated with your CPU, there is a list of fonts installed, browser release version, OS version, the list goes on. You got to jump thru a million hoops to avoid leakage, and if you do it well enuf they might not let you log in.

The Membrane Domain's Cybersecurity Center

The Philadelphia Spirit Experiment Publishing Company
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