A square based pyramid is a three-dimensional geometric shape that has a square base and four triangular faces that meet at a single point called the apex or vertex. It is a type of pyramid, which is a polyhedron that has a base and three or more triangular faces that meet at a point above the base (the apex) . A square pyramid has five faces, including four triangles and one square as the base. If the apex of the pyramid is directly above the center of the square, it is a right square pyramid with four isosceles triangles; otherwise, it is an oblique square pyramid. When all the edges have the same length, the four triangular faces become equilateral, and therefore it forms an equilateral square pyramid. A square pyramid can be used in architecture, and an example of a building that resembles the shape is the Egyptian pyramid. It can also be used in chemistry as a molecular structure, a square pyramidal molecular.