Lee begins by establishing very deep details about the setting. She does much more than tell us what Maycomb looks like and who is there; she tells us the history of Maycomb from when it was founded. This history gives us a sense of the importance of heritage and the past to the characters. In addition, Lee weaves Maycomb history throughout the book.
An example of this is when Miss Caroline, Scout's first grade teacher, is introduced in chapter two:
“This says I am Miss Caroline Fisher. I am from North Alabama, from Winston County.” The class murmured apprehensively, should she prove to harbor her share of the peculiarities indigenous to that region. (When Alabama seceded from the Union on January 11, 1861, Winston County seceded from Alabama, and every child in Maycomb County knew it.)
Little details like this show us how important where you are from is to the people of Maycomb. It is significant to the story's plot and themes. Scout learns she has to give people the benefit of the doubt. Her father explains to her that Miss Caroline is not from Maycomb and doesn’t know Maycomb’s ways, and Scout has to learn to look at things from Miss Caroline's perspective.
Like Miss Caroline, the reader is a Maycomb outsider. As Scout fills her in on the way things work in Maycomb, we learn a lot, too. Lee has developed a rich world, with generations of Cunninghams, tense race relations, and a backdrop of the Great Depression.
There was no hurry, for there was nowhere to go, nothing to buy and no money to buy it with, nothing to see outside the boundaries of Maycomb County. But it was a time of vague optimism for some of the people: Maycomb County had recently been told that it had nothing to fear but fear itself (Chapter 1).
We are also told Maycomb has one main residential street, which makes it easy for a lot of action to happen there with all the key characters present. Examples of this are the mad dog and the fire. The rest of the time, Scout and Jem just interact with people and we learn a lot about Maycomb and its residents, especially Maycomb’s resident boogeyman Boo Radley, through their Scout and Jem's playtime.