Jean Louise Finch is the daughter of widowed lawyer Atticus Finch. Known affectionately by her nickname, Scout is nearly six years old as the story begins. A tomboy through and through, Scout is eager, inquisitive, and observant. Her father teaches her to read at an early age, so she has the ability to soak up information wherever she finds it. She is mature and wise far beyond her years, which doesn't always sit well with the adult citizens of Maycomb. Even at six Scout shows herself to be open-minded and openhearted. She sees people as individuals and does not prejudge them according to the color of their skin. Scout goes into situations expecting as much goodwill as she brings, and has difficulty coping with deceit. By the book's end when she is nine, she learns to deal with the fact that the world is not as kind or honorable as she grew up believing.
Jeremy Atticus Finch (Jem) is Scout's older brother, 10 years old at the novel's beginning. He is as wildly imaginative and curious as Scout, especially when it comes to the reclusive Boo Radley, but he also has the capacity to be thoughtful and considerate. Jem is more introspective than other boys his age, perhaps because he misses his mother (who died three to four years before the events of the book). Jem's thoughtfulness is characterized by a deliberate and deep ability to think. At times we see the youthful Jem at war with the Jem who is growing up; this dichotomy, or split personality, makes his character all the more real.
Atticus Finch is a lawyer in Maycomb, Alabama, and the widowed father of Jem and Scout. Atticus is well-respected personally and professionally. He is an honest man with an open heart, a quick and fair mind, and a gentle disposition. At the same time Atticus is strong and focused in everything he does. His levelheadedness and legal training give him a solid backbone and strength of conviction, particularly during Tom's racially fueled rape case. Neighbor Miss Maudie tells Jem and Scout that Maycomb citizens are paying a great compliment to their father by placing faith in him to do the right thing. Throughout the novel Atticus shows himself capable of living up to that trust.
Calpurnia has been the Finch family cook since Jem was born. When Atticus's wife died, she became a mother figure of sorts for the kids and a strict disciplinarian. Atticus considers her an integral member of the family. Her presence gives Jem and Scout insight into the African American community and a greater understanding of the racial tension in Maycomb. Calpurnia is a strong character, a bit like a female version of Atticus. While she may not have extensive formal schooling, she has gained much wisdom from life's experiences. She, like Atticus, isn't quick to judge, a rare quality in the racially divided town of Maycomb. Calpurnia serves as a bridge between the black and white communities. She knows Tom Robinson, which makes the case all the more personal for Atticus.
Arthur Radley, or Boo, is the reclusive neighborhood legend who becomes the object of Jem, Scout, and Dill's obsession over the summer. He lives three doors down from the Finches in a foreboding house, where he hasn't been seen for years. According to local lore Boo's father kept him imprisoned in the house after Boo got into legal troubles as a teenager. The children's fear and prejudice against Boo runs parallel with the town's prejudice against Tom Robinson, the black man accused of raping a white woman. But the real Boo is quite a different person than the town believes. By the end of the novel the children have a more nuanced and sympathetic opinion of the former object of their curiosity and fear.
Charles Baker Harris, or Dill, is the six-year-old nephew of Rachel Haverford, the Finches' next-door neighbor. Jem and Scout meet him at the beginning of the novel when he comes to stay for the summer. Dill becomes a good friend to both Jem and Scout, and Atticus and Calpurnia regard him as one of their own. Dill, who is being shuttled among relatives after his mother remarries, protects himself with a vivid imagination. When he hears the story of Boo Radley, he entices Jem and Scout to help him lure the reclusive Boo from his house.
Bob Ewell is the father of Mayella Ewell and Tom Robinson's accuser. He is jobless, racist, and tends to drink away the relief checks that are meant to feed his many children. As the trial unfolds he becomes even more belligerent and vicious toward Atticus Finch for defending Tom Robinson. He is a racist because it gives him someone to look down on; he has no softness, no kindness, and no goodwill. He is unable to see the value of pulling himself up, even when the opportunity presents itself. In particular he has great feelings of inferiority, which, in this case, are aroused by Tom Robinson, who says at one point in the trial that he feels sorry for Mayella Ewell because she has no one to help her. Out of ignorance, Bob Ewell finds Tom Robinson's compassion for his daughter an insult to him and his family.
Tom Robinson is the black man accused of raping Mayella Ewell. A good-hearted man of about 25, Tom is married, has children, and is known to be honest and hard-working. It is Tom's misfortune to be living in proximity to the Ewells. When Mayella Ewell asks for his help with small tasks, he obliges because he knows her father never helps her. Unfortunately it's Tom's thoughtfulness that puts him in Bob Ewell's sights where, like the mockingbird killed for sport, he is eventually destroyed.