Church - (from the Greek. House of the Lord) is a building or structure whose primary purpose is to facilitate the meeting of the Christian Lord. Churches are used for worship in Orthodoxy, Catholicism and in most Protestant churches. The main church of a city or monastery usually is called a Cathedral (Cathedral church). The word cathedral is also used for the name of a temple where there is the chair of ruling bishop. An Orthodox or Catholic Church have at list an altar (in Orthodoxy it is usually east-oriented) and a room for prayers. Most Protestant churches do not have altars (except for Lutheran, Anglican and some other branches). Typically an Orthodox or Catholic church is composed of several interrelated parts: a chapel, crypt side and altar.