Currently there is a flourishing world-wide interest in 'nano science' research which attempts to make and organize objects on the nanometer length scale. As a result of increasing ability to artificially assemble and condensed matter at the nanometer scale, where properties are often changed dramatically and processing high performance material for wide verity of applications is becoming possible. Continued efforts in this field may lead to the development of novel materials with technologically important properties.The properties of nano crystalline materials are very often superior to those of conventional poly crystalline materials. They exhibit increased strength / hardness, enhanced diffusivity, improved ductility / toughness, reduce density, reduced elastic modulus, higher / lower electrical resistivity depending on the material, increased specific heat, higher thermal expansion coefficient, lower thermal conductivity, superior soft magnetic properties, etc., in comparison to conventional materials. New concepts of nano composites are also being investigated with special emphasis in ceramic composites to increase their strength and toughness.