Documentation files, which are in Latex format, all contain a .tex extension and begin with a prefix of one of the following: vmd, ig, pg, or ug. Files with a vmd prefix are used by all the Guides; files with the remaining prefixes are used only by that particular Guide. For all files except the main driver Latex files for the Guides and the Book, the filenames contain a hyphen after the prefix and a concluding descriptive word. No capital letters are used. Examples:
vmd_macros.tex
pg_chapters.tex
ug.tex