A regular polygon is an n-sided polygon in which the sides are all the same length and are symmetrically placed about a common center (i.e., the polygon is both equiangular and equilateral). Only certain regular polygons are "constructible" using the classical Greek tools of the compass and straightedge. The terms equilateral triangle and square refer to the regular 3- and 4-polygons, respectively. The words for polygons with n>=5 sides (e.g., pentagon, hexagon, heptagon, etc.)...
