White dwarf is the final evolutionary stage of all stars whose mass is not too large. These are very small, faint stars which have undergone gravitational collapse and possess no energy since fusion reactions no longer occur. The faint luminosity of these stars is due to the emission of thermal energy. These stars are very dense with the density ranging from107-1011 kg/m3. These stars primarily consist of electron degenerate matter and are generally made of carbon and oxygen although some white dwarfs may be composed of neon and helium also. The composition of the White Dwarf will vary depending upon the initial mass of the star. Electrons are removed from the constituent atoms and it is the pressure exerted by these densely packed electrons which prevents further contraction of the star. White dwarfs were first noticed in the year 1910 and were given the name ‘White Dwarf’ in the year 1922 by William Luyten. When a star has become a white dwarf its temperature is higher than 100,000K. After about a billion years of its formation its temperature can be of the order of 6000K. Over a long period of time white dwarfs emit all their energy and begin to radiate in the red band of the spectrum. Finally they cool down to temperatures at which their radiation is no longer visible and become Black Dwarfs.