Dance Dance Revolution, or DDR, (ESRB rating: E) is a series of popular video games originating in Japan, and popular around the world. It started out as an arcade game and is commonly played in bars and nightclubs.
The series encourages gamers to hit buttons with their feet, in time with the directions on the screen, and rewards them with "points" and encouraging messages, such as the word "PERFECT!" The game features many songs for the players to dance to, including popular current or classic songs and songs created just for the game.
DDR is considered a good form of aerobic exercise, and represents a positive trend towards healthier video games.