TEX (LaTeX)
Also known as: .tex file, LaTeX source, TeX document
A .tex file is the plain-text source for a TeX or LaTeX document — a markup language used to typeset technical and academic writing. You compile the .tex with a TeX engine to produce a polished PDF, especially for math-heavy papers.
- Plain-text source for TeX/LaTeX typesetting
- Compiles to PDF; standard for academic papers
- Tiny text file; auxiliary outputs are disposable
How TeX and LaTeX work
You write a document as plain text marked up with commands — for sections, equations, citations, and figures — in a .tex file. A TeX engine (such as pdfLaTeX or XeLaTeX) then compiles that source into a finished PDF.
LaTeX is a set of macros on top of TeX that makes this practical, and it is the standard for math, physics, and computer-science papers because it renders complex equations and references beautifully.
Files and storage
The .tex source is a small, human-readable text file you can edit in any editor. Compiling it produces a PDF plus auxiliary files (.aux, .log, .toc) that you can safely delete and regenerate.
A LaTeX project can also pull in image and bibliography files, which are the parts that take real space. The .tex files themselves are tiny.