Galaxy on the Brink
The Jedi Order is an ancient monastic peacekeeping organization unified by its belief and observance of the Force, specifically the Light Side. The Jedi were the guardians of peace and justice in the Galactic Republic, and became the most famous of the various groups that relied on the Force for their power. Led by a series of Jedi Councils, though there is usually one master that the entire Order looks to for guidance, called a Grand Master, the Order grew over the millennia despite facing many trials, most often threats from the Sith, wielders of the dark side of the Force.
A Jedi would begin as a Youngling. When it was time for them to start their training, and they qualified, they would begin training as a Padawan. Then when they were finished training, they would take the Jedi Trials, and become a Jedi Knight. After training a Padawan, they were usually accepted into the levels of a Jedi Master.