Note 1:There are 7 crystal systems on the basis of axis of symmetry.
Note 2: A. Bravais shows that all possible three dimensional space lattice are of fourteen distinct types. These fourteen lattice types are derived from seven crystal systems
1.Cubic System : a=b=c and α = β = γ = 90° Examples : NaCl, Zinc blende, Cu ,Diamond, Silver and Cesium chloride
2.Orthorhombic system: a≠b≠c and α = β = γ = 90° . Examples :Di mercury dichloride, ammonium sulphate and Iodine.
3.Tetragonal system: a=b≠ c and α = β = γ = 90° . Examples : Rutile TiO2 and lead tungstate.
4.Monoclinic system: a≠b≠c and α = γ =90°β ≠ 120° . Examples :Potassium chloride and high temperature form of sulphur.
5.Rhombohedral system: >a=b=c and α = β = γ ≠ 90° .Examples :Arsenic, antimony, bismuth and calcite.
6.Triclinic system: a ≠ b ≠ c and α ≠ β ≠ γ ≠ 90° . Examples :Boric acid
7.Hexagonal system: a=b≠c and α = β = 90°γ = 120° Examples :Graphite