Are There Any Conditions That Apply to Slavery?

The conditions of slaves have varied across world history, both during the period of their servitude and they became freedmen. It seems to me that three conditions are virtually universal. First, slaves were not members of the family that owned them. Second, slaves were expected to perform some kind of work or provide some kind of service. And third, they were legally tied to their owners, so that they couldn't just quit and find another job.