Originally posted by: Nemesis77
Didn't read the thread in detail, but....
In the ancient times, elvish blacksmiths created the Rings off Power. Three for elves, seven for dwares and nine for mortal men. But their work was corrupted by Sauron, who created the One Ring. He poured large part of his power in to the ring, and as long as the ring survived, Sauron wouldn't really be defeated.
The ring gives it's owner power over the other rings and the thigs that were made with those rings. In reality that means that it gives te ruler of the One Ring power over the world. It's lesser power is that it turns the wearer of the ring invisible. The One rong doesn't have power over the three elvish rings, because those are hidden from Sauron.
Kami already gave brief description of Sauron, but here's some more. In the beginning, Valar created the world together with Ilúvatar in the Music of The Ainur. But during The Creation, Melkor, one of the Valar, corrupted the creation. He turned against the other Valar, and he was cast out and given the name Morgoth (The despised). Morgoth came to Middle-earth and enslaved it. Sauron was Morgoths servant. Eventually Morgoth was destroyed in The War of The Silmarils. All this happened long before LOTR takes place. If you want to read abou it, go read Silmarillion.
You could say that Valar = Gods, Maiar = angels. Then who is Ilúvatar? He (she? It?) has always existed. He was before anything else.