A state bar association is an bar association that represents or seeks to represent all of the attorneys in a specific U.S. State.
A Mandatory or Integrated bar association is one to which a state delegates the authority to regulate the admission of attorneys to practice in that state; typically these require membership in that bar association to practice in that state.
In the other states, membership in the bar associations is voluntary.
There are many other bar associations, typically organized by geography (e.g. county bar associations), area of practice, or affiliation (e.g. ethnic bar associations).