__title line 1__
__title line 2__

__what this page explains and why it matters, 2-4 sentences__

Drag the model on the right to rotate it. The button in each chapter makes that event actually happen in the model.

1__chapter title__

__Body, 2-3 paragraphs. Explain each term in one line when it first appears.__

__one-sentence gist of this chapter__

2__chapter title__

__body__

  1. __step description. Match the numbers in say().__
  2. __step description__
  3. __step description__

__gist in one sentence__

Glossary

__term__
__one- or two-sentence definition__

Sources (checked __YYYY-MM-DD__)