Yoshizawa–Randlett system

Models are typically classified as requiring low, intermediate or high skill depending on the complexity of the techniques involved in the construction.

The diagrams in this book were very unclear, and often only showed the result of the folding process, leaving the folder unsure how the model was created.

These ranged from an unwieldy set of symbols to a photograph or sketch of each step attempting to show the motion of a fold.

This system caught the attention of Samuel Randlett and Robert Harbin, who added a few symbols such as “rotate” and “zoom in”, and then adopted it as the standard.

The two main types of origami symbol are lines and arrows[2]— arrows show how origami paper is bent or moved, while lines show various types of edges: The operations shown here are all fairly common.