Jedi robes can only be worn by Jedi classes, but require no Armor Proficiency.
According to the Messages - Feedback window, the Defense Bonus of all Jedi robes is summed under feats and effects, which is restricted to a maximum defense bonus of +10. For example, a Jedi wearing a Jedi Master Robe (+3) and using Master Speed (+4) and Force Armor (+6) only receives a defense bonus of +10, not +13.
Although the Description windows for Jedi robes display Max Dexterity Bonus like armor, according to the Messages - Feedback window this restriction does not actually apply. Hence even though all Jedi robes display Max Dexterity Bonus: +8, Dexterity modifiers greater than +8 are still added to defense in their entirety.
This means Jedi normally wear robes instead of armor, particularly since many Force powers are restricted when wearing armor.
Jedi Robe
Members of the Jedi Order typically wear plain or unassuming garments.
Jedi Knight Robe
Members of the Order typically wear plain or unassuming garments, but this variant offers the additional protection needed by Jedi influencing important events.
File:KotOR Item Dark Jedi Knight Robe.png Dark Jedi Knight Robe
Designed for those who relish personal combat, and know that power comes to those who take it, these robes offer good protection with no hindrance to movement.
Jedi Master Robe
Members of the Order typically wear plain or unassuming garments, but Jedi Masters also know the importance of adequate protection when great challenges must be surmounted.
Dark Jedi Master Robe
These robes offer superior protection while still allowing full freedom of movement. They are the robes of the true masters, those whose will and authority go unopposed.
Qel-Droma Robes
The Force is strong in the Qel-Droma blood, and many of the family have joined the Jedi Order over the centuries. These robes were created as a gift for Cay Qel-Droma during the war against Exar Kun, and it is said that only one who truly walks the path of the light can wear them. Cay himself wore the robes in his duel against Ulic Qel-Droma, his brother who had fallen to the dark side. Cay was slain in the battle, but his death at his brother’s hand would eventually lead to Ulic’s redemption. These powerful robes then passed down to Duron Qel-Droma, Cay’s cousin, when he joined the Jedi. But Duron disappeared shortly after the time of the Great Hunt, and the robes were lost with him.
Star Forge Robes
Created by the mystical technology of the Star Forge, these robes focus the inherent Force abilities of the wearer, fueling their power. Although the Star Forge itself is an artifact of the dark side, these robes were customised using an analysis of the Jedi they were created for, resulting in a powerful light side item that the Jedi can safely use against their enemies without fear of taint or corruption.
Darth Revan’s Robes
Created by the mystical technology of the Star Forge, these robes focus the dark side energies of the wearer, fueling their power. The Sith Lord Darth Revan was wearing similar robes when captured by the Jedi, who viewed the garments as an abomination and destroyed them. However the Jedi Council, not being familiar with the origins of the robes, were unaware that the Star Forge would be capable of producing an item of such terrible power a second time.