The Force is a form of living energy that was first discovered and used by the Jedi Knights. The Jedi have a powerful command of the Force, which allows them to manipulate gravity fields, sense emotions and impulses, and communicate with beings on other energy fields, including the dead.

In the decades before the war, Jedi were recognized at an early age and taken to various study planets where they were trained to use the Force correctly. Any species could capture Jedi energy, provided that their blood is compatable. It was important that potential Jedi be recognized at an early age, for if they weren't, it was likely that they would discover their powers on their own and use them incorrectly.

Jedi who abuse the powers of the Force, known as Sith, are said to belong to the Dark Side of the Force. Emotions such as fear, anger, and hate lead Jedi down the path to the Dark Side and it is belived that once a Jedi ventures down that path, they will forever be guided by evil.

When Anakin Skywalker submitted to the Dark Side of the Force, becoming Darth Vader, he and the Emperor began hunting down the Jedi until all of them were wiped out except for Master Yoda who took refuge on Degoba, and Obi-Won Kenobi who relocated to Tatoonie, awaiting the time when Luke Skywalker would come of age.

As a rule, Jedi are not supposed to submit to their emotions, especially those that lead to the Dark Side. Jedi are also not encouraged to love, a quality which makes Luke Skywalker unique, due to his passion for Wizera.

Although enemies, Darth Vader hopes to convert Luke to the Dark Side, exploiting his emotions. Luke, however, believes that there is good in Vader, remanance from Anakin Skywalker.

Jedi training is intense and involved, often taking years at a time. Luke Skywalker, due to his obligations to the Rebellion, takes his training in shifts, often months apart. Jedi Master Yoda is the only Jedi left with the knowledge of how to train young Jedi. He hopes that Luke and Leia as well will be able to finish their training before he dies.