Mars is the fourth planet in our solar system. It is the second largest planet (excluding dwarf planets) in the solar system, after Mercury. It has two small moons named Phobos and Deimos. An abundance of iron oxide gives Mars its red color. Mars is home to the largest volcano in the solar system, Olympus Mons.
A list and description of the planet Mars in fiction can be found here.
The name Mars comes from the Roman god of War. In 2014 34 boys were named Mars in the U.S.