Robert Anson Heinlein was an American science fiction writer. Often called "the dean of science fiction writers," he was one of the most popular, influential, and controversial authors of the genre. Heinlein set a high standard for science and engineering plausibility and helped raise the genre's standards of literary quality. He was one of the first writers to break into mainstream magazines such as The Saturday Evening Post in the late 1940s with unvarnished science fiction. For many years, Heinlein, Isaac Asimov, and Arthur C. Clarke were known as the "Big Three" of science fiction.

Heinlein's works often posed provocative situations that challenged conventional social mores. His work continues to influence the science-fiction genre and modern culture. Works like Stranger in a Strange Land and Starship Troopers helped mold archetypes and explore themes like plural marriage and militarism. Heinlein used his science fiction to explore social and political ideas and speculated on how science and engineering might shape the future of politics, race, religion, and sex.

Heinlein was named the first Science Fiction Writers Grand Master in 1974. Four of his novels won Hugo Awards, and seven of his works were awarded "Retro Hugos." In his fiction, Heinlein coined terms like "grok" and "waldo" and popularized others such as "TANSTAAFL" and "space marine."