= Crystal system
A <crystal system> classifies crystals by their point-symmetry properties. The conventional three-dimensional classification has seven systems: triclinic, monoclinic, orthorhombic, tetragonal, trigonal, hexagonal, and cubic.
This is distinct from counting the fourteen <Bravais lattices>, which also distinguish allowed lattice centerings. A unit-cell drawing gives a convenient coordinate description, but symmetry, rather than merely an arbitrary choice of cell lengths, determines the crystal system.
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