From Wikipedia: Zoo Tycoon 2 is a video game in which the player may create and operate a zoo by managing its finances, employees and animal exhibits. The goal is to become a "zoo tycoon". There are a number of gameplay modes in the game, and each has differing limitations. A Freeform game in Zoo Tycoon 2 allows you to create the zoo of your choice, the only restrictions being space, animals and objects.... In addition to Freeform mode, there is also a Campaign mode in which the player chooses a campaign to play through and is placed in the shoes of an average zoo owner and is assigned different goals to complete; these goals may include having to breed tapirs, train dolphins, rescuing abused animals and more. As well, there is a Challenge mode in which the player has a limited amount of money (although the player can choose their starting amount) with which goals must be completed.