In general a cone is a pyramid with a circular cross section. A cone is a three-dimensional geometric shape that tapers smoothly from a flat, usually circular base to a point called the apex or vertex.

Specifically it is the solid figure bounded by a plane base and the lateral surface formed by the locus of all straight line segments joining the apex to the perimeter of the base.

Often the term cone refers to just the surface of the solid figure or just to the lateral surface. The axis of a cone is the straight line that passes through the apex, about which the lateral surface has a rotational symmetry.

The volume

*V* of any conic solid is one third of the product of the area

*B* of the base and the height

*h* that is the perpendicular distance from the base to the apex.

The center of mass of a conic solid of uniform density lies one-quarter of the way from the center of mass of the base to the vertex, on the straight line joining the two. Thus a three dimensional cone of a pyramid can be calculated on the basis of this formula.