Bob Gellman writes:
The vast and ever increasing collection of information about consumers by search engines, advertisers, data brokers, web merchants, and myriad other online and offline companies raises many concerns. A website that stores (and reads) your emails, records every search you make, knows what addresses you look for on its maps, and holds your documents may know more about you than any other single institution, perhaps even including your family members.
Imagine if your email provider reads your email – or some other data accumulator reads your tweets or social network page – and tells the airlines that you are going to a family funeral across the country. Suddenly, you only find that airlines only offer you seats at a very high price. Think that you can hide your identity by searching before you sign in to buy? Doubtful. Web trackers likely know who you are using IP addresses, cookies, or other tricks invisible to most users.
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