Canons regular are priests who live in community under a rule ( and canon in greek) and are generally organised into religious orders, differing from both secular canons and other forms of religious life, such as clerics regular, designated by a partly similar terminology. Preliminary distinctions All canons regular are to be distinguished from secular canons who belong to a resident group of priests but who do not take public vows and are not governed in whatever elements of life they lead in common by a historical Rule. One obvious place where such groups of priests are required is at a cathedral, where there were many Masses to celebrate and the Divine Office to be prayed together in community. Other groups were established at other churches which at some period in their history had been considered major churches, and (often thanks to particular benefactions) also in smaller centres. As a norm, canons regular live together in communities that take public vows. Their early communities took vows of common property and stability. As a later development, they now usually take the three public vows of chastity, poverty and obedience, although some Orders or congregations of canons regular have retained the vow of stability. By 1125 hundreds of communities of canons had sprung up in Western Europe. Usually, they were quite independent of one another and varied in their ministries. Especially from the 11th century, among the canons regular, various groupings called congregations were formed, which partly resembled religious orders in the general modern sense. This movement parallelled in some respects the kind of bonds established between houses of monks. Among these congregations of canons regular, most adopted the Rule of St. Augustine, hence taking their name from St. Augustine, the great Doctor of the Church, "for he realized in an ideal way the common life of the Clergy". They became known as Augustinian Canons, and sometimes in English as Austin Canons (Austin being a form of Augustine). Where it was the case, they have also been known as Black Canons, from their black habits. Nevertheless, there have always been canons regular who never adopted the Rule of St. Augustine. In a word, canons regular may be considered as the genus and Augustinian Canons as the species. Otherwise put, all Augustinian Canons are canons regular, but not all canons regular are Augustinian Canons. In Latin, terms such as Canonici Regulares Ordinis S.