\documentclass{article}
 
\begin{document}
All LaTeX input files conform to a certain structure, illustrated here.
The first command above specifies the type of document you intend to create. 
The article class provides a good all-purpose layout.

This is a new paragraph (just leave a blank line.) 
many short lines
like these
are joined to make a paragraph. LaTeX does not start a new output
line until it encounters a blank line (new paragraph) or you force
a new line by inserting double backslashes.\\ Now this will be
a new line in the output.

% is the comment character. LaTeX ignores from the % to the end of the line.

\end{document}  % Don't forget the \end{document}!