The circular economy is an alternative to the linear "take-make-dispose" system that aims to be restorative and regenerative by design. There are two types of material flows - biological materials that can return to the biosphere and technical materials that are kept at high value through reuse. The circular economy requires changing the entire operating system, not just individual products, and analysis shows it can also make economic sense for manufacturers compared to the linear model. Some manufacturers have already adopted circular design and business models in their products.