Eastern Christians have a shared tradition, but they became divided (schism) during the early centuries of Christianity in disputes about christology and fundamental theology.
In general terms, Eastern Christianity can be described as comprising four families of churches the Assyrian Church of the East, the Eastern Orthodox Churches, Oriental Orthodoxy, and the Eastern Catholic Churches.
Although there are important theological and dogmatic disagreements among these groups, nonetheless in some matters of traditional practice that are not matters of dogma, they resemble each other in some ways in which they differ from Catholic and Protestant churches in the West. For example, in all the Eastern churches, parish priests administer the sacrament of chrismation to newborn infants just after baptism; that is not done in Western churches. All the groups have weaker rules on clerical celibacy than those of the Latin Rite (i.e., Western) Catholic churches, in that, although they don't allow marriage after ordination, they allow married men to become priests (and originally bishops). For these reasons, it sometimes makes sense to generalize, saying "In the Eastern Church, it is customary to ..." etc.
