On the LaTeX document preparation system based on the TeX typesetting language. Note that http://tex.stackexchange.com is specifically dedicated to (La)TeX related questions.
LaTeX is a document preparation system based on the TeX typesetting language developed by Donald E. Knuth. LaTeX was first developed by Leslie Lamport in 1985 and is available as free software under the LaTeX project public license. LaTeX is thus short for Lamport TeX.
There is a Stack Exchange site dedicated to LaTeX, which is a good place to ask any (La)TeX-related questions.
A great many problems can be solved by selecting the right existing macro package from CTAN.