Superginats are types of starts, characterzied by being the biggest starts.
When supergiants die (run out of hydrogen) the originate a supernova than they either become a neutron star or a black hole:
→ A black hole is a place in space, in timepsace to be more precise, that is most commonly known for its dark colour and for its drastical gravitational influence.
→ A neutron star is a very little but dense star, composed by neutrons and turns out to be the core of the dead supergiant.
Hope it helped,
BioTeacher101