What Is Nihilism?

Nihilism is the belief that all values are baseless and that nothing can be known or communicated. A true nihilist would believe in nothing, have no loyalties and no purpose other than perhaps an impulse to destroy. There's a lot of ambiguity here, but the most common thing that I can find is that idea that life is meaningless. Typically nihilists don't believe that there's any sort of God out there. We're on this one little rock in a vast universe.