The characters are split into the "bad" characters, who represent hypocrisy and excessive concern with outward appearances, and the "good" characters, who live honestly and authentically, full of love for God, nature and other people, embodying the virtues of humility and simplicity.
The "bad" characters include minor characters such as Heidi's Aunt Dete and the housekeeper Fraulein Rottenmeier.
The "good" characters are more important and central: they include Heidi and Alm-uncle, her grandfather, who has tried to live a more geographically isolated life to escape society's hypocrisy. Others include characters, major or minor, whose physical or outward disabilities only magnify their inner goodness, such as Peter's blind grandmother and the "crippled" (or, as we would say, disabled) Clara Sesemann.
Peter stands out as a "mixed" character. He can be lazy and jealous, but he is loyal and wedded to the simple life. He is the one character to undergo personal transformation, learning to rely more on prayer and to become more forgiving.