In "To Kill a Mockingbird," explain what Atticus means when he says a mob is always made up of people.
A mob in itself often seems to have a mind and a momentum all of its own. We see this many times throughout history. We also see it in chapter 16 of To Kill a Mockingbird when an irate lynch mob descends upon the jail to get hold of Tom Robinson. Mob lynchings were, tragically, common across the South during the first half of the twentieth century, so there's nothing particularly unusual about the events in Maycomb.
Atticus bravely resists the mob, but it's the way he does this that matters. Atticus always encourages his children to put themselves in the shoes of other people so they can gain a better understanding of them: that's just what he does here. He doesn't look at the enraged mob outside the jailhouse as a thing, but as a collection of people—people he knows, people he meets almost every day of his life. And because they're individuals, it's possible to make them snap out of their mob mentality.
Scout understands this herself, which is why she ends up convincing Mr. Cunningham, as an individual, that it would be wrong for him to hurt her father. By establishing a connection with him, Scout is able to separate Mr. Cunningham from the mob consisting largely of people Scout doesn't recognize.
Atticus is referring to the fact that despite the mob mentality that develops, even the most dangerous mob is constructed of individual people, people who can sometimes be reasoned with when reminded who they are. For example, outside the jail where Tom Robinson is being held, Scout engages Walter Cunningham's father in friendly and innocent conversation about Walter, and about the money owed her father, even as the mob around him prepares to possibly harm her father, who is there to protect the prisoner Tom. As Scout continues to chat, she is reminding Mr. Cunningham of the friendly relationship between Atticus and Mr. Cunningham even as Mr. Cunningham is unable to pay his bill with Atticus: "Let that be the least of your worries," is how Atticus put it. When one is forced to look at oneself as an individual, it can break through the mob mentality that can cause a person to forget him or herself and do things he or she wouldn't normally do.