How is atmosphere portrayed through the character of Boo Radley in To Kill a Mockingbird?

At the beginning of the novel, Boo's character provides an
atmosphere of mystery and fear, especially for the children. Boo has not left his home since he
was a teenager, and gossip is consistently spread about him. Many of the adults of Maycomb have
not tried to stop the rumors about Boo, and some adults have even spread the rumors themselves.
Jem, Dill, and Scout spend their summer trying to lure Boo out of his house, and Scout stops
playing this game when she hears laughter from inside the house. The childrens' fear has been
fostered through the prejudice and ignorance of the same townspeople who want Tom Robinson
convicted of rape. As the novel progresses, Boo's true character begins to shine through, showing
him to be a gentle soul, just like Tom Robinson. If not for Boo, Jem and Scout would have been
killed by Bob Ewell.