Texdoc is a command line program to find and view documentation in TeX Live. Its primary function is to locate relevant documentation for a given keyword (for instance, a LaTeX package name) on your system, and open it in an appropriate viewer.
The web site texdoc.org is an online TeX and LaTeX documentation lookup system, which uses the Texdoc utility as its backend. It provides a user-familiar web interface and also RESTful API for developers.
You can browse texdoc's documentation online (both pdf): user manual and short man page.
Texdoc is part of the TeX Live distribution.
(A command named texdoc is also available in MiKTeX, but it is merely a shortcut for
an independent program, mthelp.)
Please use the texdoc mailing list for any discussion, such as bug reports (such as finding the wrong file for a given keyword), feature requests, patches, etc. You don't need to subscribe to the list in order to post a message or receive replies. The list archives are public.
It is also fine to post issues to the bug database.
Texdoc development is hosted on github.
Texdoc is currently maintained by Takuto Asakura, Karl Berry, and
Norbert Preining. The current Lua incarnation of Texdoc was primarily
written by Manuel Pégourié-Gonnard. First
texlua versions by Frank Küster. Earlier shell script
versions by Thomas Esser, David Aspinall, and Simon Wilkinson, with
contributions from Reinhard Kotucha.
Texdoc is free software. It is distributed under the terms of the GNU GPL, version 3 or later, as of version 0.42. Earlier versions were in the public domain.