The core of a neutron star is primarily composed of a superfluid mixture of neutrons, superconducting protons, and a small fraction of electrons, with the density reaching about ten times that of an atomic nucleus. As one moves deeper into the core, the percentage of neutrons increases significantly compared to protons and electrons. The matter is believed to be devoid of empty space, filled instead with tiny electromagnetic vortices. Additionally, conditions in the core suggest the presence of a quark-gluon fluid, which may help explain the differences in mass between neutron stars and black holes. Understanding these fundamental properties is crucial for further research in astrophysics.