The Catholic Church (Latin: Ecclesia Catholica), commonly called the Roman Catholic Church,[note 1] is the largest Christian church, with an estimated 1.28 to 1.41 billion baptized members worldwide as of 2026. It consists of 24 autonomous (sui iuris) churches—the Latin Church and 23 Eastern Catholic Churches—organized into nearly 3,500 dioceses and eparchies governed by bishops. Throughout history, the church has had a large role in the development of Western civilization. Catholic communities are present worldwide through missions, immigration, and conversions. The majority of Catholics live in the Global South, reflecting rapid demographic growth in Africa, Asia, and Latin America, as well as secularization in parts of Europe and North America. Catholic doctrine is rooted in the Nicene Creed and holds that the church is the "one, holy, catholic and apostolic Church" founded by Jesus Christ.[8][9][note 2] It teaches that bishops are the successors of the apostles and that the pope—the bishop of Rome—is the successor of Saint Peter the Apostle, entrusted with a unique and primary pastoral role. The pope serves as the head of the church; the Diocese of Rome forms his local jurisdiction, while the Holy See serves as the church's central governing authority through the Roman Curia. Apostolic teaching is understood to be transmitted through Scripture and sacred tradition, interpreted by the magisterium, the church's teaching authority. Catholic liturgical life includes the Roman Rite, other rites of the Latin Church, and the liturgical traditions of the Eastern Catholic Churches. Religious orders, monastic communities, and lay movements contribute to a wide range of theological and devotional expressions within Catholicism globally.[12][13] Among the church's seven sacraments, the Eucharist is seen as the source and summit of the Christian life and is celebrated in the Mass. Catholics believe that through consecration by a priest, the bread and wine become the body and blood of Christ. The Virgin Mary is venerated as the Mother of God and honored through dogmas such as the Immaculate Conception, perpetual virginity, and Assumption, including devotional practices.[14] Catholic social teaching emphasizes care for the poor, the sick, and the marginalized. The church operates tens of thousands of educational, medical, and charitable institutions worldwide, becoming the largest non-governmental provider of education and health care. Catholic (from Greek: καθολικός, romanized: katholikos, lit. 'universal') is first attested as an adjective used to describe the church in the early second century.[19] The first known use of the phrase "the catholic church" (Greek: καθολικὴ ἐκκλησία, romanized: katholikḕ ekklēsía) appears in a letter written around AD 100 by Ignatius of Antioch to the Smyrnaeans,[note 3] which reads: "Wheresoever the bishop shall appear, there let the people be, even as where Jesus may be, there is the universal [katholike] Church."[20] In the Catechetical Lectures (c. 350) of Cyril of Jerusalem, the name "Catholic Church" was used to distinguish it from other groups that also called themselves "the church".[20][21] The "Catholic" notion was further emphasized in the edict De fide catolica, issued in 380 by Theodosius I, the last emperor to rule over both the eastern and western halves of the Roman Empire, when he established the state church of the Roman Empire.[22] Since the East–West Schism of 1054, the Eastern Orthodox Church has taken the adjective "Orthodox" as its distinctive epithet; its official name continues to be the "Orthodox Catholic Church".[23] The Latin Church was described as "Catholic", with that description also denoting those in communion with the Holy See after the Protestant Reformation of the 16th century, when those who ceased to be in communion became known as Protestants.[24][25]