According to astrophysicists, stars have life cycles that, depending on the size of the star, can end with a star becoming a black dwarf, a neutron star, or a black hole. The higher-mass stars (at one point red supergiants) can ultimately end with a massive explosion called a supernova, which can lead to them becoming a neutron star, a stage in a star’s life in which the protons inside of it have been converted into neutrons. Or the remnants of the explosion can become a black hole, a region (rather than an object) from which nothing can escape. Of course, these are theories and not a whole lot has been unmistakably proven.
One Too Many Mornings and a Thousand Miles Behind 