Tracking The Companies That Track You Online and Some Tips on How to Block: NPR
One of the fastest-growing online businesses is the business of spying on Internet users by using sophisticated software to track movements through the Web, so that the information can be sold to advertisers.
Julia Angwin recently led a team of reporters from The Wall Street Journal in analyzing the tracking software. They discovered that nearly all of the most commonly visited websites gather information in real time about the behavior of online users. The Journal series identified more than 100 tracking companies, data brokers and advertising networks collecting data — which are then sold on a stock market-like exchange to online advertisers…
…”The company tracking Ashley knew all of her favorite movies, her age, her hometown and that she liked quizzes and entertainment news. … She was given an ID number, which was stored on her computer in something called a cookie. And a cookie is a text file on your computer and really just gives you an ID. And often times when you visit a website, these cookies are installed without you knowing it. So she had an ID number in her cookie. Separately, when she went to some websites they had a different kind of technology called a beacon, which is another invisible kind of tracker that runs some software while you’re on a page and tries to figure out what you’re doing on that page. So in her case, this beacon was actually seeing her activity around movies in particular — she had listed her favorite movies on a website — and it saw that she was typing those in, and captured that data and stored it in a profile, which is stored at some mother ship where there’s a little drawer that has her ID number, and inside the drawer it says, ‘These are her favorite movies.’ And every time they find more information about her, they add more to the file.”