The architecture of the Indian rock-cut temples, particularly the sculptures, were widely adopted in South Indian, and Indianised architecture of Cambodian, Annamese (Khmer) and Javanese temples (of the Greater India). In any study of Angkorian architecture, the emphasis is necessarily on religious architecture, since all the remaining Angkorian buildings are religious in nature. During the period of Angkor, only temples and other religious buildings were constructed of stone. Non-religious buildings such as dwellings were constructed of perishable materials such as wood, and so have not survived. The religious architecture of Angkor has characteristic structures, elements, and motifs, which are identified in the glossary below. Since a number of different architectural styles succeeded one another during the Angkorean period, not all of these features were equally in evidence throughout the period. Indeed, scholars have referred to the presence or absence of such features as one source of evidence for dating the remains.