Classification,+Comparison+and+contrast+-+Version+2

=**Polygons**=

**Classification**
The polygons are classified by the number of sides, convexity and symmetry.

Number of sides: the polygons are named with a prefix that means how many sides it has(for example mono-, di-, tri-), and the suffix make reference to a characteristic of the polygon (like tri-angle, or quadri-lateral) and, if does not have a especial characteristic it will be use the suffix -gon (wich means that the figure is a polygon). For example:
 * Monogon, have one side.
 * Digon, have two sides.
 * Triangle, have three sides and three angles.
 * Quadrilateral, have four sides.
 * Pentagon, have five sides.

Convexity: the polygons may be simples or complex:


 * 1) Complex: it is complex if two of their consecutive edges cross between them.
 * 2) Simple: if two of his no consecutive edges do not cross between them. The simples are classified in:
 * Concave: it is concave if a crossing line could cut the polygon in more than two points.
 * Convex: it is convex if a crossing line could cut the polygon in a top of two points. Also the convex are classified in regular or irregluar.
 * Regular convex: those are the ones that have equal sides and equal angles.
 * Irregular convex: those are the ones that have at least one side or angle different than others.

Symmetry: the polygons can be classified by symmetry in (all of them are simple, convex and regular):
 * Equiangular: those are the ones who have all the angles of the same size.
 * Equilateral: they are those who have the same size of their sides.
 * Cyclic: those does not have rectangular corners, all of them are curves.

In the previous classification are some comparison and contrast, between the number of sides (comparison) and in the convexity part are some contrasts (between the types of simples ones).