\documentclass{standalone}

\usepackage{tikz}
\usepackage{shapes}

\begin{document}
\begin{tikzpicture}
  \grid{7}{11}{(-3,-3)}

  \square{green}{(-1,3)}
  \square{green}{(2,2)}

  \disk{cyan}{(0,0)}

  \disk{magenta}{(1,5)}

\end{tikzpicture}
\end{document}