The universe contains many diverse and exotic bodies that we are only beginning to understand. Among the countless exotic bodies, the one that is arguably the most elusive is the black hole. In astronomy, there are many theories and questions about black holes. The subject of these investigations has been the properties, processes, effects and function of black holes. Even today, scientists still don't completely understand black holes because they are very difficult to detect. According to the definition, a black hole is a region of space where the collapse of matter results in a gravitational field so intense that not even light can escape. This is because black holes are capable of bending space-time to extremes. Because of this rather unique effect on spacetime, there comes a point where the curvature of spacetime becomes infinite. Additionally, this point can be calculated mathematically for black holes. Indeed, this point was calculated in 1915 by Karl Schwarzschild and is called singularity. However, the existence of black holes had been predicted long before that time. The first idea of ​​a black hole was proposed by a geologist named John Michell in 1783. It was then proposed again by the mathematician Laplace in 1796. It was around this time that Laplace coined the term "black stars" in reference to the idea of ​​black holes. However, the idea of ​​black holes was largely rejected at that time because the effect of gravity on light was not understood. Then, in 1915, Albert Einstein introduced his theory of general relativity which managed to prove that gravity has an effect on the propagation of electromagnetic radiation. It was at this point that Karl Schwarzschild was able to find a solution to Einstein's problem...... middle of article ......974 when he was able to use the quantum field theory to show that black holes do indeed emit particles. radiation similar to that of a black body. In other words, he was able to show that black holes are not really black. Additionally, this decade also marked the detection of the first good black hole candidate. Astronomers determined that the binary X-ray star Cygnus X-1 was a black hole by observing its effect on its companion star. By observing this effect, astronomers were able to determine that Cygnus X-1 is compact and has a mass well above the maximum stable mass of a neutron star. In 1994, the Hubble Space Telescope provided the best evidence of the presence of supermassives at the centers of galaxies. More recently, researchers at Johns Hopkins University provided the first visual evidence of the existence of black holes by publishing images of a red giant engulfed by a supermassive black hole..