Example: Valentine heart

% Valentine heart
% Author: Alain Matthes
\documentclass{article}
\usepackage[usenames,dvipsnames]{xcolor}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
    \draw[ball color=BrickRed,shading=ball] (4,1) ..controls +(120:2cm)
        and +(90:2cm) .. (0,0) .. controls  +(-90:2cm) and +(90:3cm) ..
        (4,-8) .. controls +(90:3cm) and +(-90:2cm) ..(8,0)  .. controls
        +(90:2cm) and  +(60:2cm) .. (4,1);
\end{tikzpicture}
\end{document}