A financial bubble, also known as an economic bubble or an asset bubble, is characterized by a fast, large climb in the market price of different assets. This rapid growth, though, is relatively short-lived—like the bursting of a bubble—and it abruptly reverses course, dragging asset prices down with it, sometimes even lower than their original levels. Typically, a bubble is created out of sound fundamentals, but eventually exuberant, irrational behavior takes over, and the surge is caused by speculation—buying for the sake of buying, in the hopes prices continue to rise.