LaTeX2e is a document preparation system implemented as a macro package for Donald E. Knuth's TeX typesetting program.
LaTeX was originally conceived by Leslie Lamport.
This updated LaTeX reference is by no means complete, but it's a first step towards a more complete LaTeX reference! We welcome if we'll get pointed to missing commands or even better when you make additions and further improvements and send them to the authors.
TUG (TeX User Group) and DANTE (German TeX User Group) both have excellent FAQ's which answer many questions or give great pointers to additional resources both on the internet or in books. Most if not all missing packages can also be found on the CTAN servers.
This reference is not meant to replace the package documentation or the standard literature like the LaTeX handbook and the LaTeX companion. Look there for detailed descriptions of the commands and even mostly more options and examples.
The authors intend to extend this documentation to other TeX related packages (e.g. ConTeXt, MetaPost, Metafont, etc.). Contributions are very welcome!