\documentclass{article}

\usepackage{times,epic,eepic}

\begin{document}

\begin{picture}(300,300)

% co-ordinate system
\put(0,0){\vector(1,0){300}}
\put(0,0){\vector(0,1){300}}
\multiput(10,-2)(10,0){29}{\line(0,1){4}}
\multiput(-2,10)(0,10){29}{\line(1,0){4}}

% a point
\put(30,60){\circle*{3}}

% a line. Note that \line does not work well for small line segments at
% an angle; use \path of length one instead. You could use \path all the
% time instead of \line.
\put(100,100){\line(2,1){50}}

% a circle
\put(200,200){\circle{50}}

% some text with top right-most corner at the co-ordinate
\put(200,60){\makebox(0,0)[tr]{DM45 rocks!}}

% a path
\path(10,10)(20,11)(30,13)(40,16)(50,20)(60,25)(70,31)(80,38)(90,46)

\end{picture}

\end{document}