To Kill A Mockingbird is a coming of age novel, which means that it follows a young adult through a traumatic even that leads directly to his or her maturation into an adult. Scout, the young narrator in the novel, reaches this point by the end of the novel. At the beginning of the story, Scout is very young and naive; she doesn't understand how Tom Robinson, clearly innocent, could be found guilty for a crime that he didn't commit. She doesn't understand Boo Radley or his strange behaviors. By the end of the novel, however, she has changed.
After the conviction and suspicious death of Tom Robinson, Scout understands what it means to be a "mockingbird" in her society, and at the end of the story, she wants the world to treat these people with equality and respect. When Atticus and Mr. Tate determine that Boo Radley won't be tried for the murder of Mr. Ewell, Scout says to Atticus, "It'd be sort of like shootin' a mockingbird, wouldn't it?" She understands that a trial and public scrutiny of Boo Radley would be cruel and unnecessary suffering, when all he had done was save the children.
Later, when she walks Boo Radley home, she makes another important observation. Atticus had always told her that "you never really know a man until you stand in his shoes and walk around in them." She notes that "just standing on the Radley porch was enough."
At the end of the novel, the plot has resolved. Scout doesn't literally need or want anything; however, with the realizations she had throughout the text, the reader can gather that Scout craves more equality and justice in the world for the proverbial "Mockingbirds."