TeX is standard software for high-quality rendering of paper documents in the Unix world. It was written by the famous Don Knuth ( WikiPedia:Donald_Knuth), probably the most prominent IT expert of our time.
ProWiki can use TeX to render mathematical formulas. See CdmlTeX for syntax, examples and for the installation instructions of the subsystem.
LaTeX is a popular macro package to make TeX easier to use. So if you have LaTeX installed then you also have TeX installed. ProWiki just needs the TeX components.