A triangular pyramid has four vertices. A square pyramid has five vertices. Other pyramids have a greater number of vertices depending on the shape of the base.
In geometry, a vertex is defined as an angular point of a polygon or a polyhedron. In two dimensions, this means a point where two lines meet, such as the points of a triangle. In three dimension, it means the point where three lines meet, such as the corner of a cube. While the most common pyramids have triangular or square bases, a pyramid can be constructed using any convex, simple polygon as a base, such as pentagons or hexagons. In all cases, the total number of vertices is equal to the number of vertices, or corners, the base has plus one more for the point at the top where all the faces meet.