Modular origami is a paper craft where individual sheets of paper are folded into identical shapes and fitted together to create a larger shape. It is part of a larger family of paper crafts originating in Japan, with the earliest examples of the modular style appearing to date to around the 1700s, when they began appearing in origami instruction books. The distinctive feature of modular origami, separating it from other kinds of origami, is the use of identical modules in the construction of a complex larger shape.
To make modular origami, people can use a pattern book or develop their own patterns. Modules are made by folding sheets of paper as desired, leaving tabs and pockets to fit them together. When the modules are carefully fitted together, the tension holds the finished piece together, with the push and pull of each module working to keep the whole integrated unless it is firmly tugged. Sometimes, a different shape will be used inside to create attachment points and add structure, although some people believe this means the finished project is no longer an example of modular origami.
This paper folding art is highly reliant on math and mathematical patterns, as people need to be able to visualize shapes and how they will fit together in the finished product, whether it is flat or three dimensional. Students being introduced to mathematical concepts might have modular origami projects to work on for the purpose of illustrating ideas and providing people with hands-on reinforcement of classroom lessons. Some mathematicians make a hobby of working on modular origami, trying to devise more complicated and interesting shapes with modules of varying styles.
Instruction booklets for modular origami are available. They include everything from detailed instructions on how to make specific pieces to general guidelines on designing and folding modules, allowing people to develop their own shapes and projects of interest. Some booklets also come with origami people to get started, or people can buy their own origami sheets. Cutting paper for custom applications is another option; people can experiment with things like old maps and other papers for visually interesting finished pieces.
Modular origami usually ends up both lightweight and sturdy. People can use it for creating mobiles, display pieces, ornaments, or even projects like lamp shades, depending on the size of the finished project. If origami is being used to make a lamp shade, it is important to create room for the bulb and a ventilation hole to allow heat to escape, so fires will be prevented.