The typical role of a bishop is to provide pastoral governance for a diocese.[16] Bishops who fulfill this function are known as diocesan ordinaries, because they have what canon law calls ordinary (i.e. not delegated) authority for a diocese. These bishops may be known as hierarchs in the Eastern Catholic Churches. Other bishops may be appointed to assist ordinaries (auxiliary bishops and coadjutor bishops) or to carry out a function in a broader field of service to the Church, such as appointments as papal nuncios or as officials in the Roman Curia.