In the earliest of days, before the Valar entered Arda, Sauron was originally known as Mairon the Admirable, a powerful Maia of Aule the Smith, a Vala. However, Mairon was soon corrupted by the Dark Lord Morgoth an evil Vala and Dark Enemy of Arda, and turned evil, taking the name, “Sauron.” At first, he was a spy for Morgoth, telling him the Valar’s doings.
Carcharoth lived in the First Age of the Sun, the greatest werewolf who ever lived, a beast of the line of Draugluin. He was created as a defence against Huan, and was reared by Morgoth's own hands on living flesh and filled with great power. So Carcharoth grew to great size and his strength seemed beyond compare. His eyes burned like red coals and his teeth were poisoned as the spears of the Orcish legions.
“Hador Lórindol, son of Hathol, son of Magor, son of Malach Aradan, entered the household of Fingolfin in his youth, and was loved by the King. Fingolfin therefore gave to him the lordship of Dor-lómin, and into that land he gathered most of the people of his kin, and became the mightiest of the chieftains of the Edain. In his house only the Elven-tongue was spoken; but their own speech was not forgotten, and from it came the common tongue of Númenor.”
“Few ever changed [Fëanor’s] courses by counsel, none by force. He became of all the Noldor, then or after, the most subtle in mind and the most skilled in hand.” ~ The Silmarillion, Of Fëanor and the Unchaining of Melkor. (Artwork: Fëanor Curufinwë by koyak)