Creative is a world in which is filled with certain sized plots, to obtain one of these plots you can either go to an empty plot of your choice and type in this command "/plotme claim" or if your not picky in which plot you receive you can simply run this command "/plotme auto", Within these plots you can build what ever you can imagine aslong as it stays within the size of your plot.

 

Here are some pictures of the Creative world and some of the creations that people have made: