The most basic definition is unwanted or useless materials. Waste is generated during the extraction or processing of raw materials, the consumption of final products or other human activities. The Basel Convention (treaty designed to reduce the movement of hazardous waste between nations) and the EU define waste as substances or objects that are disposed of, intended to be disposed of, or required to be disposed of by international law. While the United Nations states that "wastes are materials that are not produced for the market, which the user has no further use in terms of his/her own purposes of production, transformation or consumption, and for which she/he wants to dispose."