example-3.2.tex

\documentclass{article}

%% Denote paragraphs with vertical space rather than indenting (not critical)
\usepackage{parskip}

%% Support for URL in introductory text (not needed for main example)
\usepackage{url}

%% *** Enable TikZ ***
\usepackage{tikz}


\begin{document}

%% Introductory Text
Example 3.2 from the book\\
\emph{Unlocking LaTeX Graphics: A Concise Guide to Ti$k$Z/PGF and PGFPLOTS}.\\
For more information, visit \url{https://latex-graphics.com}.
\par\bigskip

%% *** START OF EXAMPLE CODE ***
\begin{tikzpicture}[every node/.append style= {purple,draw,thick,fill,fill opacity=0.8}]
  \draw[help lines] grid(3,3);
  \node (A) at (1,1) {}; % empty node
  \node (B) at (2,2) {}; % empty node
  \draw (A) -- (B);
\end{tikzpicture}
%% *** END OF EXAMPLE CODE ***

\end{document}