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I figured i might as well research into the qualities of a star, hence here we are.

This is the general life cycle of a star, "with about the same mass as the sun" (1.989E30 kg), according to 'astronomy for dummies'.

1 - Gas and dust in a cool nebula condense, forming a young stellar object (YSO)
2 - The YSO disperses its remaining birth cloud as it shrinks and the hydrogen ignites. (nuclear fusion is beginning)
3 - As the hydrogen burns the star begins the main sequence
4 - After using all the hydrogen in the core, the shell ignites.
5 - With the shell burning, the energy released due to the fire causes the star to expand and glow brighter. The expanding makes the surface; cooler, larger and redder, meaning the star has become a red giant.
6 - The stellar winds that blow off the star remove the outer layers over time,this forms a planetary nebula around the remaining core.
7 - the nebula then expands, dissipates, leaving a mere core.
8 - Now a white dwarf star, the core cools and fades.

Before i explain that, it should be noted that stars with a higher mass than the sun have a different life cycle; they explode as supernovas and leave neutron stars or black holes instead of producing nebulae and dying as white dwarfs. Also the life cycle of a star with a mass greater than the sun only lives a few million years being exploding, whereas the sun may last for around 10 billion years.

The stars with a mass lower than that of the sun can't really have what is called a life cycle, they begin the same, as YSO, before joining the main sequence as normal, however they never progress past red dwarfs. (When I say never, a red dwarf burns its hydrogen fuel so slowly it won't run out. Admittedly it could, if given long enough,but that length of time is greater than the age of the universe at present, hence every red dwarf that has ever existed still exists.) What happens is that because the smaller the mass, the less fierce the fire, the longer it lasts; although I may be oversimplifing stellar astrophysics. But that is the core principle, as the opposite is true also; the bigger the mass, the fiercer and faster the fire.