What is a polygon?

A polygon is a form in Geometry.  It is a single dimensional plane made of connecting lines and any number of vertices.  It is a closed chain of connected line segments or edges.  The vertices of the polygon are formed where two edges meet.  Examples of polygons are hexagons, pentagons, and octagons.  Any plane that does not contain edges or vertices is not a polygon.  An example of a non-polygon is a circle.