Choose Your Own Adventure is a series of children's gamebooks where each story is written from a second-person point of view, with the reader assuming the role of the protagonist and making choices that determine the main character's actions and the plot's outcome. The series was based upon a concept created by Edward Packard and originally published by Constance Cappel's and R. A. Montgomery's Vermont Crossroads Press as the "Adventures of You" series, starting with Packard's Sugarcane Island in 1976.
Choose Your Own Adventure, as published by Bantam Books, was one of the most popular children's series during the 1980s and 1990s, selling more than 250 million copies between 1979 and 1998. When Bantam, now owned by Random House, allowed the Choose Your Own Adventure trademark to lapse, the series was relaunched by Chooseco, which now owns the CYOA trademark. Notably, Chooseco does not reissue titles by Packard, who has started his own imprint, U-Ventures.
Source: Wikipedia, "Choose Your Own Adventure", available under the CC-BY-SA License.