👉 In geometry, a tetrahedron is a polyhedron composed of four triangular faces meeting at a common vertex. It has four vertices and six edges. The vertices are called the vertices or points of the tetrahedron, and the edges are called the edges of the tetrahedron. The tetrahedron can be classified into two types: right-angled tetrahedron (also known as an oblique tetrahedron) and oblique tetrahedron