Carnival is a fixed shooter arcade game created by Sega in 1980 and has the distinction of being the first video game with a bonus round. It is similar to Exidy's 1977 Circus arcade game. The goal is to shoot at targets, while carefully avoiding running out of bullets. The targets that scroll across the screen, in rows that alternate going from left-to-right and right-to-left. Targets include rabbits, ducks, owls, and bonus items. If the duck targets from the bottom row aren't shot, they eventually come to life and begin descending towards the bottom of the screen in a zig-zag pattern. If a duck reaches the bottom of the screen without being shot first, it will eat some of the player's bullets. Objects also periodically appear among the targets that will give the player extra bullets when shot. A spinning wheel with eight pipes sits above the rows of moving targets; all the pipes must be shot before the round can end.
At the end of each round, the player receives bonus points for all bullets remaining in his supply. He then plays a bonus round, where a large white bear with a target walks across the screen. Each time the bear is shot, it rears up for a second, then begins walking more quickly in the other direction. The object is to shoot the bear as many times as possible until it escapes off the screen. Following the bonus round, the next wave begins.
In higher levels, there are more duck targets and fewer extra bullet targets, putting a premium on accurate shooting. The game ends when the player runs out of bullets.
The tune that plays throughout the game is Sobre las Olas (Over the Waves) by Juventino Rosas, a tune commonly associated with carnivals and funfairs.
Source: Wikipedia, "Carnival (arcade game)," available under the CC-BY-SA License.