In geometry and crystallography, a Bravais lattice, studied by Auguste Bravais (1850), is an infinite array of discrete points generated by a set of discrete translation operations described by:
where ni are any integers and ai are known as the primitive vectors which lie in different directions and span the lattice. This discrete set of vectors must be closed under vector addition and subtraction. For any choice of position vector R, the lattice looks exactly the same.
A crystal is made up of a periodic arrangement of one or more atoms (the basis) repeated at each lattice point. Consequently, the crystal looks the same when viewed from any of the lattice points.
Two Bravais lattices are often considered equivalent if they have isomorphic symmetry groups. In this sense, there are 14 possible Bravais lattices in three-dimensional space. The 14 possible symmetry groups of Bravais lattices are 14 of the 230 space groups.
Read more about Bravais Lattice: Bravais Lattices in At Most 2 Dimensions, Bravais Lattices in 3 Dimensions, Bravais Lattices in 4 Dimensions