While centered (unarmored, unencumbered, and either unarmed or wielding monk weapons such as the kama, quarterstaff, or shuriken), you get an increase to your attack bonus, and a 2% dodge bonus at monk levels 1, 2, and 4 for a total of 6%. The attack bonus increase starts at 1 (at level 1) and increases by +1 for every four additional monk levels.
Some rare items are enchanted as 'Ki Weapons' and can be used with your monk abilities, and certain feats and enchancements can further expand the list of weapons available to your monk.
Notes
This feat compensates the BAB progression of a monk, with the result that the effective attack bonus progresses like a fighter.