Heidi (; German: [ˈhaɪdi]) is a work of children's fiction published between 1880 and 1881 by Swiss author Johanna Spyri, originally published in two parts as Heidi: Her Years of Wandering and Learning (German: Heidis Lehr- und Wanderjahre) and Heidi: How She Used What She Learned (German: Heidi kann brauchen, was es gelernt hat). It is a novel about the events in the life of a 3-year-old girl in her paternal grandfather's care in the Swiss Alps. It was written as a book "for children and those who love children" (as quoted from its subtitle).
Heidi is one of the best-selling books ever written and is among the best-known works of Swiss literature.
Source : Wikipedia