* The [[Roman Catholic Church]] (approx. 1.1 billion baptized members) traces its roots back to [[Saint Peter]] whom Catholics believe was appointed as the first leader of the church by [[Jesus Christ]] and the succession of [[Pope]]s as the spiritual leaders of Christendom.
* The [[Orthodox Church]]es (approx. 300 million baptized members) trace their roots back to the Apostles, in the five ancient patriarchates of the undivided Church of the first millennium of her history, known as the [[Pentarchy]],<ref>[https://orthodoxwiki.org/Pentarchy Pentarchy (orthodoxWiki.org)]</ref> and are organized in [[Autocephalous]] national or regional churches in communion with each other. The Pentarchy consisted of the Churche Church of [[Rome]], first in dignity of honor, [[Constantinople|Church of Constantinople]], [[Church of Alexandria (Coptic)|Alexandria]], [[Church of Antioch|Antioch]], and [[Church of Jerusalem|Jerusalem]]. Differing theological perspectives and the growing development of the doctrine of [[Petrine primacy]] in the Church of Rome led to the [[Great Schism]] between the Roman Catholic Church and the Eastern Orthodox Churches in A.D. 1054.
[[Image:Anglican Christ Church.jpg|thumb|right|200px|Anglican Christ Church in Western Australia]]
* [[Protestantism]]: the largest Communions are the [[Anglican Church|Anglicans]] (approx. 115 million baptized members) and the [[Lutheran]] World Federation (approx. 68 million baptized members). Protestantism has its origins in the European [[Reformation]]. The Protestant movement broke from the Roman Catholic Church under [[Martin Luther]] when differences over the nature of [[faith]] and works in the role of [[Christianity#salvation|salvation]], as well as other practices of the Catholic Church that Luther saw as unBiblical, were raised. Within Protestantism are four major branches: