Robert Anson Heinlein was an American science fiction writer. Often called the "dean of science fiction writers", he was one of the most influential and controversial authors of the genre in his time. He set a standard for scientific and engineering plausibility, and helped to raise the genre's standards of literary quality.
He was one of the first science fiction writers to break into mainstream magazines such as The Saturday Evening Post in the late 1940s. He was one of the best-selling science fiction novelists for many decades, and he, Isaac Asimov, and Arthur C. Clarke are often considered to be the "Big Three" of science fiction authors.
A notable writer of science fiction short stories, Heinlein was one of a group of writers who came to prominence under the editorship of John W. Campbell, Jr. in his Astounding Science Fiction magazine—though Heinlein denied that Campbell influenced his writing to any great degree.