**A cone is a geometrical figure with one curved surface and one circular surface at the bottom.** The top of the curved surface is called the apex of the cone. An edge that joins the curved surface with the circular surface is called the curved edge of the cone.

If the apex of the cone lies just above the center of the circular base, it is called a right circular cone. Oblique cones do not have the apex directly above the center of the base. The curved height or slant height of the cone is called the lateral height of the cone.

The cone may be hollow or solid. The curved surface area of the cone is calculated by the formula A=?rs where r is the radius of the base, and s is the slant height of the cone. The total surface area of the cone is given by A=?r(r+s).