I definitely didn't know that much about Sauron so again, I turned to the Tolkien Bestiary by: David Day. Here is what I found out of him.
"In the Ages of Darkness, while Melkor ruled in Utumno, and in the Ages of Stars, while Melkor was chained by the Valar, Sauron ruled the evil realm of Angband. On the return of his master, and through all the Wars of Beleriand until Melkor was cast into the Void, Sauron was his greatest general. He was also called Gorthaur the Cruel, and he survived longest of all the Maiar who served Melkor. Many were the wars and holocausts through the Ages of the Lamps, Trees, Stars and Sun that Sauron survived. After the terror of the First Age of the Sun, it is said that Saruon reappeared in the Second Age in fair form and assumed the name Annatar "giver of gifts." Eventually, when he made himself Lord of the Rings, his evil spirit was revealed and war, like a black shadow, again covered Middle-earth.
In the Downfall of Numenor Sauron's body was destroyed. Yet his spirit fled to Mordor and by the power of the One Ring he made himself again a form, though he could no longer appear fair. Thereafter he took the shape of the Dark Lord and became a fearsome warrior with black armour on burning black skin and had terrible, raging eyes. But even this form was destroyed at the end of the Second Age when Mordor fell and the One Ring was taken from his hand. Yet so great was the power of Sauron's spirit that in the Third Age he again made himself a form. His spirit became manifest in the sorcerous power of one great lidless Eye. Like the eyes of all the great hunting cats of forest, mountain and plain made into one, and made entirely evil, was that Eye which was wreathed with deadly flame and ringed in darkness. But even this form depended on the power that was in the One Ring, and, in the war that ended the Third Age, the Ring was destroyed. Once more, and finally, Sauron's spirit was swept into the shadows and never again did this Maia arise."
---taken from A Tolkien Bestiary by: David Day
