Regular 2-D Shapes

These shapes are known as regular polygons. A polygon is a many sided shape. To be a regular polygon all the sides and angles must be the same.

 
Triangle - 3 Sides
Triangle		 Square - 4 Sides
Square
Pentagon - 5 Sides
Pentagon		 Hexagon - 6 sides
Hexagon
Heptagon - 7 Sides
Heptagon		 Octagon - 8 Sides
Octagon
Nonagon - 9 Sides
Nonagon		 Decagon - 10 Sides
Decagon

 

taken from: http://www.windarooss.qld.edu.au/Main_Pages/images/2D_Shapes.gif