Guide to LaTeX & Typesetting
LaTeX is a highquality typesetting system designed to produce beautiful technical and scientific documents, especially involving mathematical equations.
It is widely used in typesetting science and mathematics journals.
Tutorials
Implementations

TeXShop
TeXShop is a modern TeX editor and previewer, which is widely used with macOS.

TeXstudio
TeXstudio is a newer TeX editor available for macOS, Windows, and Linux.

ShareLaTeX
ShareLaTeX is a commercial online LaTeX editor that facilitates collaboration.

LaTeXiT
LaTeXiT is a small macOS app that allows one to quickly typeset LaTeX equations, and drag & drop them to any supporting application, such as Keynote.
Other Software

LyX
Free WYSIWYM document processor, which uses LaTeX in the background.

MathType
Commercial WYSIWYG alternative to LaTeX. Intuitive and fun to use with Apple and Microsoft products.

Word
Our Word template is a good nonLaTeX alternative, especially for short articles. The Word Equation Editor is LaTeX friendly.