\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[english]{babel}

\usepackage[dvipsnames]{xcolor}


\begin{document}

This example shows different examples on how to use the \texttt{xcolor} package 
to change the colour of elements in \LaTeX.

{\color{blue}Text colored with \texttt{\\blue}}

\noindent
{\color{red} \rule{\linewidth}{0.5mm} }

The background colour of some text can also be \textcolor{red}{easily} set. For 
instance, you can change to orange the background of \colorbox{BurntOrange}{this 
text} and then continue typing.

\end{document}