Where all the Trackers Know Your Name
Jonathan Mayer, at the Center for Internet and Society at Stanford University, explains how online trackers get sent personally identifiable information from you, as you browse the Internet — how much you smoke, what your username is, what your job is, what you drink, what day is your birthday — the information you give to a site, it then hands it over to advertising and tracking companies, for them to put in their giant databases and sell.
Even if all the data sent about you to these random ad companies is supposed to be ‘anonymous’, a lot of the time your username can still identify you even if its not precisely your name. And especially when the information is combined and triangulated, it can be pretty easy for these companies to figure out exactly who you are.