The legal process by which property is passed from a person who has died to his or her heirs is called "probate" and the usual method for determining who shall inherit the various assets entails the Court enforcing the instructions in a written document designating heirs called a "will".
Recently, in an effort to avoid some of the costs of probate, it has become popular to create a legal document called a "trust" in which instructions for distributions after death are contained and which, if properly prepared, transfers assets after one's death without court involvement (and formal probate) but which achieves intended post death distribution as effectively as a will.