% comments present explanations of used code; [] represent optional values 

\documentclass[12pt]{article}	% definition of document class (best for uor purpose is article) and size of text  [10pt , 11pt , 12pt]
\pagestyle{empty}				% pagestyle is set to empty to suppress all styles
\usepackage{amsmath}			% mathematic package for formula rendering, it's installed with LaTeX   [mathtools] 
\begin{document}
	\normalsize  				% we could change size of text and formula [tiny,scriptsize,footnotesize,small,normalsize,large,Large,huge , Huge]
		\begin{equation*}								% equation* stop formula numbering		[align* , displaymath]
			Famous Einstein formula E = m \cdot c^2;	% here goes code for formula interpretation copied from text ( from Octave )
		\end{equation*}
\end{document}