Science fiction
Space western takes ideas from books and movies about exploring the American Old West and moves them  to space in the future. These stories are often on "frontier" colony worlds (colonies that have only recently been terraformed and/or settled) serving as stand-ins for the backdrop of lawlessness and economic expansion that were predominant in the American west. Some examples are Firefly and the movie Serenity by Joss Whedon.  Anime programs like Cowboy Bebop and Outlaw Star are also Space Westerns. Han Solo from "Star Wars" is an important Space Western character.