| Description | Markup | Example | 
|---|---|---|
| newline | \\ | 
      |
| exponent | ^ | 
      \( x^2 \) | 
| union | \cup | 
      \( \cup \) | 
| intersection | \cap | 
      \( \cap \) | 
| space | ~ | 
      |
| tilde | ‘\sim’ | \( \sim \) | 
| tilde | ~ outside of TeX | 
      ~ | 
    
| backslash | \backslash  | 
      \ | 
| x over y (division) | x \over y | 
      \(x \over y \) | 
My list focuses on things that work in mathematical formulae without using a package, because that’s where I use TeX – for math expressions.
Other web pages:
- Handy LaTeX math reference
 - Render LaTeX but copy/paste will paste only a black rectangle. Does an unattractive job on my complex example.
 - Render LaTeX VERY SLOW - copy/paste of simple stuff as text works, but copy of image does not. Renders my complex example well.
 - Render LaTeX - Chrome plugin. Renders well
 
For the copy/paste problem, you can work around it by saving the image to disk, opening with Paint, and copying from Paint.
Equation that is tough to render well:
` X(u) = \sum_{n=0}^{N-1} x(n)e^{-i2\pi un/N} `
\( X(u) = \sum_{n=0}^{N-1} x(n)e^{-i2\pi un/N} \)