The classic paper airplane using a handful straight folds on a standard 8.5- by 11-inch sheet of paper is the one that most of us learn how to fold as children. It is called a dart airplane, due both to its shape and flight pattern. The reason for its broad popularity is that the dart plant is a very easy model to fold, even if you have no prior knowledge of origami. In fact, many children who make play with dart paper planes have no idea that it falls under the category of origami.