What happen in the mad dog scene?

In the "mad dog scene" from Harper Lee's "To Kill a Mockingbird," a rabid dog named Tim Johnson wanders into the neighborhood, posing a threat to the community. Atticus Finch, the children's father and a lawyer, is called to deal with the situation. He demonstrates his marksmanship by shooting the dog, revealing his hidden talent and the moral complexity of his character. This scene symbolizes the loss of innocence and the harsh realities that the children, Scout and Jem, must confront.