Supernova

A supernova is an explosion that comes after a star dies. Sometimes, instead of exploding as a supernova, it could shrink down by collapsing by its own gravity, into an infinitesimally small point known as a singulary.

A star has a few stages in its life.
 * The young stage - It starts to exist, and most of the time, it is gaining mass.
 * The 2nd stage - It is the same stage as our Sun, in which a typical star stays the same size for billions of years, just like ours.
 * The red giant - This will happen to us in something called the "Runaway Greenhouse Effect", where the star will become much bigger, due to it burning off a lot of different elements.
 * The supernova - Same as the beginning.