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Neutron stars are one of the possible products of the evolution of stars, consist-ing of the most compact form of matter with dimensions. The concentration of mass more than the solar one within about 20km, requires general relativistic description, with the equation of state governing the physics still being largely unknown. The observational analogue of neutron stars are believed to be pul-sars, which are found to rotate with periods down to » 1msec. Rapidly rotating compact objects like these, are extremely interesting for physics, since they provide conditions that could hardly be produced in a laboratory on earth. Electromagnetic radiation is, so far, the only way to observe and study these objects, with gravitational waves being the promising new window that general theory of relativity has predicted to open in the future. The recent technological achievements in laser interferometry are just enabling detection of such waves from our galaxy. Apart from sudden violent events, such as collisions between two compact obects, oscillations from single neutron stars are also a good sourc