Any shape made of straight edges/sides – many sides
Poly = many
Polly the parrots were many and everywhere.
Gon = sides
Gone are the sideburns he’d had for years.
All the above are examples of polygons.
Polygons can be convex or concave.
Polygons where all the sides are equal length are known as equilateral polygons.
Polygons where all the internal angles are equal are known as equiangular polygons.