An X-ray binary is a binary star system in which one of the stars is a compact object, either a neutron star or a black hole, and the other is a normal star. The compact object accretes matter from the normal star through its gravitational pull, producing X-rays as the material heats up and falls onto the compact object. X-ray binaries are important astronomical sources for studying the properties of compact objects and the processes of accretion and X-ray emission.
