$\LaTeX{}$ is a typesetting program that produces beautifully formatted documents from a raw text file. See here for an example with a template and resources to get started.

There are two basic components to using $\LaTeX$. You need to install:

1. The $\TeX$ packages, and
2. A $\TeX$ editor.

• Download and install MacTeX.mpkg.zip (6.0 GB).
• Go to Applications/TeX/ and run TeX Live Utility
• Actions → Update All Packages

• See the MikTeX page.

• Short Math Guide
• The Not So Short Introduction to $\LaTeX{}$