Dalton’s atomic theory proposed a simple description of matter as composed of atoms. According to the Bohr, negatively charged particle are revolving around the nucleus in a fixed orbit known as electrons and the center part called nucleus is consists of neutrons and protons. Protons have positive charge and neutrons are charge less particle. Since the electrons are revolving around the fixed orbit, there is no loss of energy. Loss or gain of energy takes place when electron jumps from one orbit to the other orbit. Rutherford’s experiment on the scattering of alpha particles led Bohr to the theory of Atomic structure that the atom consists of a positively charged nucleus at it is center. His theory is mainly based on the following postulates. A n atom consists of a positively charged nucleus at the center. The negatively charged particles known as electrons move around the nucleus in various orbits known as stationary energy levels. The electrons cannot emit radiations when moving in their own stationary levels. The Coulombarian and Newtonian forces are applicable in the domain of the atom. The electrons revolve around the nucleus in various circular orbits When an electron jumps from a higher energy level to a lower energy level, it gives out electromagnetic radiations of a particular frequency . .