Definition of Nanomaterials: The materials which have dimension in the range of mesoscopic range or nanoscopic range i.e. 1-100nm are called as nanomaterials. Some natural nanomaterials such as DNA nanomaterial which store genetic information. Nanomaterials can exist in different shapes such as nanorods, nanoflower, nanowires, nanotubes, nanobuds etc. The nanomaterials can be classified into three different categories depending on the number of directions of quantum confinement(QC). 1. Two dimensional (2D nanomaterials) Here quantum confinement occur in one direction, dimension in that direction are in nanoregime e.g. quantum well- ultrathin layer, ultrathin film. 2. One dimensional (1D-nanomaterials) Here quantum confinement occur in two directions, i.e. dimensions in this two directions are in the nanoregime. e.g. quantum wire-nanorods, nanowires, nanowhiskers, nanotube, nanofibres, nanofilamen...