 In addition, fifty years after publication, seven of his works were awarded "Retro Hugos"—awards given retrospectively for works that were published before the Hugo Awards came into existence.In his fiction, Heinlein coined terms that have become part of the English language, including grok,
waldo and speculative fiction, as well as popularizing existing terms like "TANSTAAFL", "pay it forward", and "space marine".He also anticipated mechanical computer-aided design with "Drafting Dan" and described a modern version of a waterbed in his novel "Beyond This Horizon".