Facebook, Google, and other major internet companies track clicks and use that data to provide personalized content. More and more, each person encounters a unique online world, what some experts call a "web of one." This essential resource explores what filter bubbles are and how they work. It looks at the potential downsides of filter bubbles, such as deepening political divides and the rise of confirmation bias. It offers helpful advice about how to recognize this challenge of the digital age and how to break out of the bubble.