POLYGON
In
geometry a polygon
is traditionally a plane figure that is
bounded by a finite chain of straight line
segments closing in a loop to form a closed
chain or circuit. These segments are called its edges or sides,
and the points where two edges meet are the polygon's vertices (singular: vertex) or corners.
The interior of the polygon is sometimes called its body. An n-gon
is a polygon with n sides. A polygon is a 2-dimensional example of the
more general polytope
in any number of dimensions.
http://xenontics.blogspot.com/