The game features 144 uniquely designed holes which can be played as part of a single-player campaign or part of an online tournament against gamers around the world. There are four areas, Buccaneer's Hideout, Soho, Polar Station and Ancient Valley, with four 9-hole courses in each. They progress in difficulty from Warm-up through Pro, Extreme and finally Whacky. Power-up items are often available on the courses that allow you to control the ball in various ways to improve your score. Keys (bronze, silver and gold) are earned, by winning single-player tournaments on the various courses, that allow you to purchase wardrobe items and different putters and golf balls for the five characters available to play as. Players can also create their own golf courses and then upload the course online for other players to download similar to LittleBigPlanet.
Source: Wikipedia, "Planet Minigolf", available under the CC-BY-SA License.