An Imperial Navy crew member fulfilling the role of navigator.
Within the crew of a starship, a navigator held the responsibility of guiding the vessel. Luke Skywalker was once told by his uncle, Owen Lars, during his childhood that his father worked as a navigator aboard a spice freighter. However, the truth was that Anakin Skywalker was a Jedi Knight who participated in the Clone Wars. (Nevertheless, Anakin did possess such a vessel.)
Navigating through the Unknown Regions, referred to as the Chaos by its inhabitants, presented significant dangers due to phenomena like supernovae, black holes, gravity wells, and other peculiar occurrences. These dangers rendered navigation computers unreliable within the Chaos. Consequently, the species residing in the Unknown Regions relied on Force-sensitive navigators, individuals with the Force power of precognition, for guidance. Without Force-based navigation, journeys involved numerous short hyperspace jumps between star systems, a slow method referred to as "jump-by-jump".
Among the Chiss, Force-sensitive children served as navigators known as Ozyly-esehembo, which translates to "sky-walkers" in Cheunh. Most ozyly-esehembo were girls, and their precognitive abilities invariably diminished as they reached adulthood. The Chiss termed precognition as "Third Sight" and the rarer telepathy as "Second Sight". Although considered civilians, ozyly-esehembo served alongside caregivers in the sky-walker corps of the Chiss Expansionary Defense Fleet. The Ozyly-esehembo were among the most valuable and closely guarded secrets of the Chiss Ascendancy, with knowledge of their existence generally limited to Fleet vessel command staff and high-ranking Aristocra.
Other species in the Chaos also employed Force-sensitive navigators to facilitate hyperspace travel. This practice was so widespread that these navigators established the Navigators' Guild, offering their services to various factions and organizations within the Unknown Regions. These navigators referred to the Force as the "Great Presence". Sub-groups within the Guild included Vector One, the Pathfinders, and Void Guides. Given the Chiss Ascendancy's secrecy surrounding their sky-walkers, particularly from other Chaos societies, and the limited number of ozyly-esehembo, the Ascendancy often contracted navigators from the Navigators' Guild for journeys in the Unknown Regions.
During the Imperial Era, Galactic Emperor Sheev Palpatine sensed a disturbance in the Force emanating from the fringes of the Unknown Regions. Palpatine dispatched his enforcer Darth Vader and Grand Admiral Thrawn to investigate the disturbance's origin. Thrawn and Vader discovered Grysk forces abducting ozyly-esehmbo for navigation purposes, as well as preparing to invade Imperial territory. Their investigation resulted in the Imperial–Grysk conflict, including the rescue of several young ozyly-esehembo from the Grysk Hegemony's captivity. During this mission, Darth Vader gained the ability to navigate using the Force, inspired by suggestions from Thrawn, who originated from a society that utilized a Force aspect for navigation.