All rights reserved . Please read our Privacy Policy . Space figures are figures whose points do not all lie in the same plane. In this unit, we'll study the polyhedron , the cylinder , the cone , and the sphere .
Polyhedrons are space figures with flat surfaces, called faces , which are made of polygons .
Prisms and pyramids are examples of polyhedrons. Cylinders, cones, and spheres are not polyhedrons, because they have curved, not flat, surfaces. A cylinder has two parallel, congruent bases that are circles. A cone has one circular base and a vertex that is not on the base. A sphere is a space figure having all its points an equal distance from the center point.