In order to show a person's strength in the Force, the Jedi Order placed a set of ranks/levels for Jedi to progress through. Each one meant different responsibilities and a different potential in the Force.

Youngling:

Youngling / Initiate / Apprentice This is an unofficial title and a rank. This refers to a child with Force potential (also referred to as a "Jedi Hopeful"). Youngling is just Galactic slang for children of any sort. At a very young age, the Jedi initiates are brought from their homes and are assigned to a group for training. If a youngling is not chosen by a Jedi Knight to be their Padawan by thirteen years of age, the youngling is placed into another, lesser role in the Jedi Services. Depending on where the student's talents lay, this may be the Agricultural Corps, the Medical Corps, or the Exploration Corps.

Jedi Padawan:

A Jedi Padawan is an apprentice who undergoes intensive one-on-one training under a Jedi Knight or Master after graduating from the academy. As tradition, a Human Padawan grows a long strand of braided hair that is finally cut off during the ceremony of knighthood, when a Padawan becomes a Jedi Knight. A Jedi may have only one apprentice at a time, and is required to promote the current apprentice before taking another. Some Jedi Masters took more than one Padawan at a time if it was allowed of the Jedi Council, but was extremely rare. Some Dark Jedi and Jedi took two or more Padawans against the wishes of the council.

This rank practically disappeared during Luke Skywalker's masterhood in his Jedi Praxeum on Yavin 4. The equivalent for a Padawan was a Jedi apprentice. The term Padawan was reintroduced sometime between 40 ABY and 130 ABY.

Jedi Knight:

Disciplined, experienced Padawans may become full-fledged Jedi once they have completed "the trials," which are usually intensified tests, physical and otherwise, of candidates' skills, knowledge, and dedication. The trials resemble around the Trial of the Flesh, the Trial of Courage, the Trial of Skill, and the Trial of Spirit. Occasionally, performing an extraordinary (usually heroic) act can earn a Padawan learner Jedi Knight status, such as when Obi-Wan Kenobi, toward the end of his training, defeated Darth Maul, Dark Lord of the Sith, during the Battle of Naboo. Jedi Knight is the most common rank of Jedi; hence, the title is also used, mostly by non-Jedi, to refer to any member of the order that has at least met the compulsory requirements of the Jedi Council.

Jedi Master:

A Jedi Knight may become a Master after successfully training a Padawan Learner to Jedi Knight status. Though this is the most common manner, it is not always the case. If the council sees that a Jedi Knight has become more powerful and has gained more knowledge and discipline in the Force, then they can be nominated by one or more council members to take the trials again. But this time, the trials will be more difficult. It should also be said that most Jedi Masters, like Qui-Gon Jinn, never become members of the Council, as it is not a requirement to be a Master. The rank can also be achieved through the performance of extraordinary deeds or self-proclamation, though the latter is extremely rare, as in the case of Joruus C'baoth

Jedi Council Member:

When a Jedi Council Member vacates their seat, the council looks for an exceptional Jedi Master to fill the empty position. Presiding Council members elect prospective candidates when openings become available. In its history, the Council has accepted Knights into its ranks, but this had become more and more uncommon by the time of the Clone Wars. While there are no explicit ranks among the Jedi Council (as it is, at least theoretically, a conclave of equals), there are clear centers of authority. Master Yoda, during his tenure on the Council, was generally regarded as the Council's senior-most member, or better known as the Grand Master, and Mace Windu as his second. During the time of the New Jedi Order, Luke's idea of "first-among-equals" position as the Grand Master is also unquestioned, if not totally agreed with. Some members were permanent, or lifetime, members while the rest served limited terms, after which they stepped down and another member would be elected to the council.

Jedi Grand Master:

Grand Master, also known as the Supreme Master, was a title used in both the Old and New Jedi Orders.

Jedi Grand Master was the title given to the acknowledged leader of the entire Jedi order. Formally known as Grand Master of the Jedi Order, only the highest-ranking Jedi Masters took the title, although how exactly one earned it is unknown. The Grand Master was apparently the "first among equals" of the Jedi High Council. Yoda held this title in the days of the Republic. After the rebirth of the Jedi, Luke Skywalker held the title including the days of the Galactic Alliance, following the Yuuzhan Vong War; although he did not fully accept the title until after the Swarm war.