Treasure Island by Robert Louis Stevenson

Traditionally considered a coming-of-age story, Treasure Island is an adventure tale known for its atmosphere, characters and action, and also as a wry commentary on the ambiguity of morality — as seen in Long John Silver — unusual for children's literature then and now. It is one of the most frequently dramatized of all novels. The influence of Treasure Island on popular perceptions of pirates is enormous, including treasure maps marked with an "X", schooners, the Black Spot, tropical islands, and one-legged seamen carrying parrots on their shoulders