Atticus Finch is an interesting hero of sorts. Normally, a hero character goes through a cycle of character development and growth. Atticus, on the other hand, is a fairly static character. Who he is and how he acts toward others remains constant throughout the novel. This isn't a bad thing though, because it allows Atticus to serve as a sort of moral compass through the entire story.
Atticus is calm in manner, wise in thought, extremely intelligent, and a model of good behavior. The people of Maycomb respect and admire Atticus for all of these reasons. Interestingly though, at the beginning of the novel both Jem and Scout are embarrassed by Atticus. They see him as a bit of an old dud of a man that doesn't do manly things like hunting and fishing.
But even when the town turns against Atticus for his defense of Tom Robinson, Atticus remains constant in his personality, demeanor, and morals. He refuses to snap back at the townspeople and simply turns the other cheek. Jem and Scout both learn to deeply appreciate Atticus's moral high ground and fair treatment of everybody, regardless of skin color.