Game of Thrones is an American medieval fantasy television series created for HBO. The series is based on author George R. R. Martin's best-selling "A Song of Ice and Fire" series of seven planned fantasy novels; HBO's overall series' title is derived from the first novel. Set in the Seven Kingdoms of Westeros, where "summers span decades and winters can last a lifetime," Game of Thrones chronicles the violent dynastic struggles among the kingdom's seven noble families for control of the Iron Throne.