LaTeX is an amazing typesetting language that I mostly use to markup various mathematical formulas. I am currently learning more about it and try to use it here in the wiki too with KaTex plugin.
For writing LaTeX I use VS Code and LaTeX workshop plugin.
The Not So Short Introduction to LaTeX
Mathpix - Take a screenshot of math and paste the LaTeX into your editor, all with a single keyboard shortcut.
My LaTeX Workflow: latexmk, ShareLaTeX, and StackEdit (2015)
PlotNeuralNet - LaTeX code for making neural networks diagrams.