Automaticity is the ability to recall facts instantly in lieu of counting on fingers or diagramming the problem.
The books that followed each attempted to build on this diagramming system, later including photographs as well as drawings.
Having so many different diagramming systems was confusing, however.
In the 1950s and 1960s, Akira Yoshizawa created a simple diagramming system that used lines and a few other basic symbols to explain origami projects.
Samuel Randlett and Robert Harbin added to his work, thus creating the Yoshizawa-Randlett System of origami diagramming.