The LaTeX typesetting system is similar to Extensible Markup language (XML) or Hypertext Markup Language (HTML). Don't let these big terms scare you away. All markup languages consist of symbols, which are used to give instructions, or describe how information is to be displayed. A Kile user does not need to know HTML or XML to use LaTeX, this is just an example.
This similarity to HTML and XML makes the LaTeX not only very flexible, but offers the advanced user the ability to compose personalized functions. It also gives users who are familiar with HTML the ability to see the similarities to the way coding for LaTeX and HTML are laid out.
Creating web pages in HTML gives the user some experience similar to LaTeX because HTML has the advantage of breaking up sections using tags like HTML, head, and body to point the user where certain information in to be located. LaTeX has a similar style, because EVERY LaTeX file must contain a preamble and body.
Preamble: A series of commands that setup the document with global command such as paper size, page numbering, dimensions of the text on the page. The command \documentclass is the only required preamble, but must be there to form a document.
Body: Any additional command that comes after \begin{document}. These commands are considered local and will end with the end of the body of the document, which is concluded by \end{document}