Star

A star is an extremely hot and large ball of burning and literally always-nuclear-fusing hydrogen and helium. Stars range from red dwarfs that if they had only a little less mass they'd be a brown dwarf to hypergiant stars with masses over 100 times our sun's mass that's about to go supernova in a few thousand years.

Stars come in 4 main types - forming stars, main-sequence stars, giant stars, and dead stars. Forming stars are stars that just formed from a nebula or a gas cloud. Main-sequence stars are normal, shining stars. Giant stars are stars that are near the end of their lifespan and has its size and luminosity greatly increased while losing mass. A dead star is a star that has ended its lifespan, they come in super-dense and very small burning "balls".