I think the biggest idea in to kill a mockingbird was the stereotypes in the story. Both the situations in the story had some type of stereotyping in it which each time they were wrong. I think that if you were to get any message from this story it is that do not judge a book by its cover.
One thing that was happening in the story was Tom Robinson was accused of a crime that he did not commit and Atticus was defending him in court. Just because Tom was african american they just believed he was guilty. Tom was really just a good married man who would never do anything wrong. Then the town people filled another stereotype of that time period of being racist. Tom was nothing like what they thought he was but the towns was exactly like what Tom probably thought about them. Bob Ewell was seen as the normal back then but he turned out to be evil. He tried to to kill jem and scout when they were just kids which shows how bad the normal was back then.
Boo Radley was also stereotyped in the book, he was seen as something that was nothing like him at all. Everyone in town thinks he some weird, mean, loner guy but really he is a kind, caring person who just doesn't like a lot of attention. Just like in the book where he left Scout and Jem presents in the tree and when he saved their lives from Bob Ewell who was going to stab them. The sheriff in the story was the only person who really saw Arthur for who he really was and that was why he covered up how he killed Bob.
There were also little not things that seemed not important in the story but I think that other people had a label put on them. Atticus is seen by people as this lawyer that wasn't really interesting but he was really a deadshot with a rifle. Also Scout is a girl who was seen as weak just because she was a girl but really she kicked their butts.
Those are the stereotypes the characters had to deal with during the book.