A plane closed figure whose sides are straight lines. The term polygon
(from the Greek poly for "many" and gwnos for "angle") sometimes
also refers to the interior of the polygon (the open area that this
path encloses) or to the union of both.
|The polygon ABCD is an irregular quadrilateral
with acute angles at A, C, and D and a
reentrant angle at B. AC and BD are its
A polygon is simple if it is described by a single, non-intersecting
boundary; otherwise it is said to be complex. A simple
polygon is called convex if it has no internal angles greater
than 180° otherwise it is called concave. A polygon
is called regular if all its sides are of equal length
and all its angles are equal. Any polygon, regular or irregular, has as
many angles as it has sides.
= 180° - (360°/sides)