Neutron stars are unique natural laboratories allowing studies of the densest configurations of matter reaching up to eight densities of atomic nuclei. Such extreme regimes open a plethora of tracks of exotic physics exclusively occurring in neutron stars. One of them is connected to a fundamental question of the modern theory of strong interaction, i.e. dissociation of hadrons and deconfinement of their constituent quarks. Appearance of a gap in the single particle dispersion relation is a distinct feature of any multifermion system with even vanishing attraction including quark matter. The most prominent manifestation of this gap is formation of a uniform superfluid matter. In the case of quark matter this gives rise to superconductivity of the so-called color charge carried by quarks. I will give an introduction to the topic of color superconductivity, its role in the phase diagram of strongly interacting matter with a special emphasis on properties of neutron stars with quark cores.
Paulo Brás, Paulo Silva, Jaime Silva