A Hello world! in LaTeX

To start a new document, just put in a blank document the following sentences:

\documentclass{article}

\begin{document}

Hello world!

\end{document}

Save as: latex_example.tex. The extension *.tex is relative to LaTeX documents.

Preferable to save the document in a separate folder, it works better for you because probably you will have a lot archives very soon, like other files, pics(*.eps, *.jpeg, *.png), pdf's, etc.

To compile in linux put in a terminal:

pdflatex your_archive.tex

and the system create a pdf version of your latex file.