To start, if you use the web to find cheap flights, you might notice an uptick in web ads for the routes you just searched for. These results aren’t just influenced by what you look up and buy online, but include related sites—even online publications where you get your news and celebrity gossip.
Some e-commerce sites have even been caught displaying different prices to different customers based on a variety of potential factors, including one’s browsing history. Believe it or not, the rabbit hole goes deeper—the device that you’re using to search the web can influence results that come

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