Even the most complex origami creation is made using the same basic folds. Each fold in this traditional Japanese folk art has a specific name and shape; artisans combine these folds in different ways to create creatures, vessels, and forms from paper. Origami paper is thin and smooth; it is designed to fold readily into whatever shape is desired. Specific origami folds include mountain, valley, triangle, book, and cupboard folds.
The paper used for origami often has one colorful side and one plain white side. This coloring serves two purposes. Having two distinct shades adds a design element to the finished piece and makes it easy for the artisan to tell one side of the paper from the other as he forms origami folds.
One of the most basic origami folds is the mountain fold. Origami paper can be folded into a mountain shape by holding two paper edges together and creasing the paper in the center. Mountain origami folds can be vertical, horizontal, or diagonal. Once folded and set upright, mountain folds resemble a small mountain or upright tent, with the crease facing up and the paper edges resting on the table.
Valley origami folds are created the same way as mountain folds. The difference between the two is the final positioning of the paper. Once creased in half, a valley fold is positioned with the crease facing down, touching the work surface and the edges facing up into the air. Mountain origami folds resemble little mountains, while valley folds resemble the letter V or a deep valley.
Triangle origami folds are also referred to as diaper or shawl folds. The paper used for origami is square, so it can be easily and cleanly folded in to many different shapes. To make triangle origami folds, the paper is folded in half diagonally from corner to corner, resulting in a triangle shape.
A book fold is just what is sounds like; the paper is folded in half to resemble a little book or pamphlet. The book fold is similar to the mountain and valley folds, but it can be held in either position. In some origami books, the mountain and book fold names are used interchangeably.
The cupboard fold is the only basic origami fold that requires two steps. The paper is first folded in half to make a rectangular-shaped book fold, then folded in half a second time to create a square. Cupboard folds are often created just to mark the center of the paper; the place where the fold lines intersect is the true center of the paper and can be used to create more complex folds.