A navigator is one who works aboard a boat, submersible vessel or space ship. They are sometimes referred to as Flight navigators. Their function is to plot courses, keep abridge of current charts, redirect a vessels course heading if needed and coordinate all other navigation-related job duties with the ship's captain. On naval vessels, a navigator often cooperates with the ship's helmsman. They usually hold the rank of ensign.
In Star Wars, the character of Chewbacca served as co-pilot and navigator aboard the Millennium Falcon, though the ship's captain, Han Solo, also plotted his own courses via his ship's navi-computer. Luke Skywalker grew up believing that his father was a navigator on a space freighter before he died. In truth, his father was once a Jedi Knight who fell to the Dark Side of the Force and became the villainous Darth Vader.
In the Star Trek franchise, a navigator works as part of the bridge crew aboard a starship. On the USS Enterprise NCC-1701, the most well known navigator was Pavel Chekov. Between 2269 and 2270, the navigator on the Enterprise was an Edosian named Arex.
In the 24th century, Ensign Wesley Crusher attended Starfleet Academy and worked aboard the USS Enterprise NCC-1701-D as its navigator.