Tiling or tessellating the plane with regular polygons

If you can cover a flat surface using only identical copies of the same shape leaving neither gaps nor overlaps, then that shape is said to tessellate the plane.

Try to tessellate the plane with copies of the polygon. Choose the number of sides, move the polygons with the white circle and rotate them with the red circle.

What can you say? Which regular polygons tessellate the plane? Why?