The closePath() method creates a
line from the current point to the
start of the path. Take a look:
Here, we start the path and move
the originating point to (10, 10)
using moveTo(). Then, we add a line
till (180, 10) using lineTo(). We
add a second line using lineTo() till
(380, 90). After this, when we close the
path using closePath(), it draws a
line from the current point, which is
(380, 90), to the starting point for
the path which was (10, 10).