Binary stars are just two stars close together the biggest is considered the A star or alpha and the smallest is considered the B star or Beta.
Pulsars is the form of a star after it dies. *boom* When it becomes a neutron star. It might be something else. A star that emits two beams of radiation that sweeps across space. The stars that does that are called Pulsars.
Quasars are close to relation to a star, they are so unusual, distant, and they move haster than anything else in the universe. It is said that quasars have black holes in their centers.
Justice's Science Blog 