supernova is an exploding star. The name originally meant a new star because early astronomers only knew that a new star not previously known had appeared in the sky. Really a supernova is a very old star that has become instable and can’t keep steady like the sun anymore.
Supernova explosions are enormously powerful and a star that has become a supernova can give off more light than a whole galaxy for the short time that it exists. The explosion drives off most of the matter that was in the star and stardust races outwards at up to a tenth the speed of light.
Interstellar material gets swept up in this powerful explosion forming a mixture where later new stars and planetary systems can develop later. Our Solar System started that way. We know that because there are heavy elements in the Solar System. Heavy elements like oxygen, nitrogen and carbon form in stars and are dispersed during a supernova explosion. Elements that are heavier than iron form during supernova explosions. The oxygen, nitrogen and carbon in our bodies and in other living things was originally in one or more stars that went supernova though Red Giant stars may produce some of these elements as well. Later when the Red Giant becomes a supernova the heavy elements are dispersed. We literally owe our lives to supernova explosions but if one happens near the earth, we're all doomed! In conclusion, the supernova can be considered a god but conservative Young Earth Creationists won't believe that we are made of elements in a supernova.
Types of supernovae
Type 1a: Occurs in a binary star system when a smaller white dwarf draws gas from its bigger companion. When the white dwarf can't take in any more mass, or exceeds its Chandrasekhar limit of 1.4 solar masses, it blows up.
Type II: The lighter layers (i.e. Helium and Hydrogen layers) of a massive star implodes into its denser layers (i.e. Neon and Silicon) and the core of said star can't hold it up, and blows away the outer shells with massive power.
Type Ib and Ic: Supernovae explosion without hydrogen.
Hypernova: A HyperNova is a type lb or lc supernova to the extreme.
Gamma-Ray Burst: Sometimes, before a massive star explodes, the core of that star collapses into a black hole. The black hole begins to devour the star from the inside out. However, not all of the star can be sucked into that black hole, so during the final moments, the black hole spews out jets of plasma from its poles. These jets produce dangerous gamma rays as they move throgh space, hence its name. The rest of the star soon explodes as a supernova (Woosley, et al, 2002).
Other causes of gamma ray bursts are also possible. 
- Supernova nucleosynthesis
- Woosley, et al. (2002). https://www.cfa.harvard.edu/events/2002/grbconf/index/speaker_presentation/woosley.pdfA
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