Called dominium or proprietas, the concept refers to the rights, privileges and powers that a “legal” person can have over something. This distinction of "legal" is also used to differentiate between a person who is enslaved. There are multiple forms of citizenship within the term "legal" but those who are not "legal" are those defined as enslaved. All of this means that as the legal concept of ownership is emerging, including the "ownership" of people, it is developed alongside the idea that there can be both “legal” and “illegal” persons. There are multiple components to the right of ownership in Roman law, including how possessions can be transferred to another person, the inherent power vested in the “head of household,” and more.