Origami, the Japanese name for the art of paper folding, comes from the Japanese verb oru (to fold) and the noun kami (paper). The word "origami" is now commonly used around the world. A finished origami figure is called a model, the method for folding a model is called a design, and drawn instructions for a model is called a set of diagrams. An origami artist is usually called a paperfolder.




The only requirement for origami is a piece of paper, making it one of the most accessible arts. Almost any paper may be used, but standard "origami paper" is thin, strong, and holds a crease very well. It is also usually white on one side and colored on the other side, and is cut into 15 cm squares (about 6 inches). Some origami artists also experiment with other materials, and have folded models out of cardboard, various types of cloth, wire mesh, sheet metal, and even sheets of pasta.




The basic technique of origami is folding, and many complex folds have been developed. The simplest fold is the valley fold, where a flat piece of paper is folded towards the paperfolder. When this fold is unfolded, the crease line forms a valley shape.




Closely related is the mountain fold, where the paper is folded away from the paperfolder. This crease line forms an upraised ridge, or a mountain shape. Since these folds differ only in direction, mountain folds are usually made by turning the paper over, folding a valley fold in the indicated position, and then turning the paper over again. Certain combinations of basic folds form bases, starting shapes that may be used to fold many different models. The four most common bases, from simplest to the more complex, are the kite base, the fish base, the bird base, and the frog base.




The names of the bases reveal that many paperfolders enjoy folding models of animals (including all living creatures). Besides the many animal models, there are models of almost all physical objects including people, faces, plants, vehicles and buildings. Some paperfolders fold abstract or mathematical shapes, and others specialize in modular origami, where many copies of a simple folded shape are assembled to form large elaborate structures.




Paperfolders are a diverse group of people ranging from artists to scientists to therapists. Artists and craftspeople use origami as a way to express themselves creatively. Scientists, architects, and mathematicians explore the geometry of origami for its own beauty and for practical applications. Therapists and teachers use origami as a tool to help their patients recover from illness or to help their students learn. Many people fold paper simply because it is fun.