A faceted gemstone has several key aspects. The table is the very top, flat, polished face of a faceted gemstone.
The crown is the general top section of the gemstone, above the girdle. The girdle is the widest point of the gemstone, and consists of a thin row of tiny facets. When viewed from above, the shape of the girdle determines the shape of the gemstone itself (oval, round, princess cut, etc). Facets are the tiny polished "faces" of the gemstone. The culet (if it exists; it's not always present) is the tiny facet on the very bottom of the gemstone.