(1) A vector field whose circulation around any arbitrary closed path is zero is called a conservative field or a restoring field. In a force field, the line integral represents work. A conservative field in this case means that the total net work done by the field or against the field on any closed path is zero. (2) A vector field whose circulation around an arbitrary closed path is nonzero is a nonconservative or nonrestoring field. In terms of forces, this means that moving in a closed path requires net work to be done either by the field or against the field.