When a right circular cone of revolution is cut by planes at different planes at different angles, four curves of intersection are obtained, they are called conic sections diagram.
While the intersecting plane is perpendicular to the axis, the resulting curve of intersection is a circle.
Whether the plane makes a greater angle along with the axis than to the elements, the intersection is an ellipse.
Whether the plane makes the same angle along with the axis as the elements, the resulting curve is a parabola.
Whether the plane makes a smaller angle along with the axis than do the elements or is parallel to the axis, the curve of intersection is as a hyperbola.