Isaac Asimov is a science fiction writer best known for his "Foundation" series, which includes "Foundation," "Foundation and Empire" and "Second Foundation." Additionally, Asimov is known for his "Robot" series, which includes "I, Robot," "The Naked Sun" and "The Caves of Steel."
The "Robot" series consists of 38 short stories and five novels. "I, Robot" is the first collection of stories, and features Asimov's "Three Laws of Robotics," which play a role in many of the other stories and novels. These laws determine the behavior of robots, stipulating that a robot cannot harm a human being, must obey orders given to it by human beings, and must protect its own existence as long as such protection does not conflict with the first or second law. These laws allowed Asimov to explore both robot-human interactions and morality.
The "Foundation" novels trace the decline and fall of the Galactic Empire in the far future, using an invented branch of science called "psychohistory." The novels explore themes such as fate and determinism, as well as the cyclical nature of history. In the stories that make up the early "Foundation" novels, a group faces a crisis with an outcome that is eventually revealed to be pre-determined, making the novels explorations of the limits of free will.