Property law overlaps with tort through trespass and nuisance law; it overlaps contract in rules governing the creation and transfer of land or of interests in land in ways that both benefits and burdens to run with the land against third persons, cumulating in the emergence of planned unit developments. It also has a transition to the law of regulation through the study of zoning and takings law. The distinctive feature of Property is the rules that govern the creation of the legal commons in air and water, and the rules of acquisition, typically by initial possession of other forms of property, chiefly land, animals and chattels. More recently, the subject deals with the creation of rights in various form of intellectual property.