A format war occurs when two incompatible versions of a similar technology begin to compete against one another in the market. This has happened many times in audio/video field, but it is not unknown on other fields of technology. Top 10 Format Wars article tells about ten of the most famous examples. In almost every case, one of the two formats wins out in the end, either because of a better marketing strategy or a superior product, leaving groups of unlucky consumers with an obsolete technology. Sometimes both formats have failed on the battle.