The Ancient Roman family was a complex social structure based mainly on the nuclear family, but could also include various combinations of other members, such as extended family members, household slaves, and freed slaves. Ancient Romans had different names to describe their concept of family, including "familia" to describe the nuclear family and "domus" which would have included all the inhabitants of the household. The types of interactions between the different members of the family were dictated by the perceived social roles each member played. An Ancient Roman family's structure was constantly changing as a result of the low life expectancy and through marriage, divorce, and adoption.