# What is the difference between LaTeX and MathJax?

This might be a silly question, but I am rather new to using LaTeX/MathJax, which I use to render chemical equations over at Chemistry SE. I tend to use the term LaTeX and MathJax synonymously, although I think that's wrong. Can anyone point me the difference between each?

• See also Comparing MathJax and MathML – TeXnician Jul 8 '17 at 10:13
• Maybe you'll find the above link informative. Against its title the answerer also explains what MathJax really is. For what's LaTeX you'll find a ton of definitions out there, mostly something like a markup language and document preparation system. – TeXnician Jul 8 '17 at 10:15
• Seems like the real difference is that LaTex works just fine on my machines, MathJax doesn't :-( I really don't understand why the developers think that it's a good idea to render text in black when the user has the background color set to black... – jamesqf Jul 8 '17 at 15:53

I'm trying to answer it in a simple way utilizing Wikipedia:

MathJax is a cross-browser JavaScript library that displays mathematical notation in web browsers, using MathML, LaTeX and ASCIIMathML markup.

That means that MathJax is a software that works in your browser on some text which is marked up using different techniques. One of them is a LaTeX-like notation. In general it is independent of usual LaTeX binaries and the most part of the markup LaTeX provides.

LaTeX on the other hand is referred to as document preparation system. It is also used as term for the markup language that's used to write the document. In general LaTeX is a) a TeX format (so the markup language) and b) an executable that processes documents in (a) into the DVI format.

"LaTeX" is used in two senses, the name of a document markup language with syntax like \section{Intro} and \frac{a}{b} but also the name of the program that implements the processing of that language to produce typeset output.

MathJax does not use the (la)tex program at all, it is a javascript program run in your web browser (or other javascript engines such as node.js) which renders various mathematical markup languages, notably a language that is essentially the math subset of LaTeX syntax, but also the MathML markup language which uses XML syntax.