Definition of face in 3D shape?

Answer 1

There is a lot ofcontroversy about this topic. Some people say that everysurface is a face and other say it's only flat surfaces. It's pretty clear in prisms ofpyramids(excluding the cone) but it get mor complicated when you get into cylinders, spheres, and cones. The best answer is, there is no definitionbecauseit's not a proper term. It would be better to talk about a base. A base is the flat surface of a shape thatappears twice of a prism, one on apyramid, twice on acylinder, and once on a cone.