Turtle graphics is a simple and quick way to learn some of the basics of computer graphics.
The turtle can rotate to change its orientation, and move forward in straight lines only to change its position. When moving, it may or may not trace its path. Thus the turtle is operating in relative polar coordinates since every command modifies its current position or current direction. The code uses the mouse position at which the user clicks the mouse button as the current position of the turtle. The initial orientation angle is set in the program.