i dont really get what they are, its not making sense that one exists
The name "quasar" is truncated from an acronym for quasi-stellar radio source.
At first, they were thought to be actual galaxies because of the amount of emitted radiation--radiation not just in the "visible light" part of the electromagnetic spectrum, but even X-rays. But, they were pointlike sources of energy as opposed to spread out galactic sources. The debate was over what could output energy like a galaxy, but was not spread out like a galaxy. A galaxy very, very far away? Since they were discovered with radio telescopes, it was the radio waves that made astronomers scratch their collective heads--and put the "r" on the end of quasar. Technology in the '80s confirmed theories that received radio waves were simply red shifted from farther up the spectrum.
More recently, because of numerous studies by various astronomers, the general consensus in the astrophysicist community is that the source of the radiation is a supermassive blackhole at a galactic center. More precisely, what is known as an accretion disc surrounding the black hole. As matter is drawn into the black hole, it does not all fall straight in perpendicularly to the surface of the black hole's event horizon. As that matter develops a spiral motion it speeds up.. a LOT. Kinetic energy is heat energy. It generates so much heat that even X-rays are emitted--sometimes even gamma rays.