  We have constructed and compared models of rotating neutron stars and strange
stars, within the Hartle framework. The significance of the low energy density
region and crust region inside the neutron star has been studied, along with
how much the existence of strange matter above the energy density 300 MeV/fm3
can affect the neutron star properties. We have confirmed several
universalities among the neutron star properties such as, dimensionless moment
of inertia vs dimensionless quadrupole moment, dimensionless tidal
deformability vs dimensionless moment of inertia and moment of inertia
parameters vs R/2M.
