The "Shape" of your Diamond is not the same as the "Cut" of your Stone
Below are a few diamond shapes that are commonly used in finished jewelry. Diamond "shape" should not be confused with diamond "cut", which is one of the four C's of diamonds. The most popular shape is the Round Brilliant Cut, which has 57 or 58 facets, depending on whether or not it has a culet, which is the point beneath the pavilion of the diamond.
In addition to these diamond shapes, there are also some "specialty diamond cuts", which are typically created as variants from the popular diamond shapes seen below.