The term supply chain refers to all organizations involved in moving a product (good or service) from its initiation/birth until it reaches its final customer, be it a consumer or an organizational buyer. A channel of distribution is a special type of supply chain. Recycling is often made part of the supply chain. Quite often only parts of a supply chain are studied at one time and the study is made from one organization's perspective. When looking from an organization towards a supplier it is called to view the chain upstream, and downstream when the view is towards the customer. Studies of supply chains include besides raw material or supplies, various types of financial transactions, knowledge exchange, adaption and social relations. Due to various reasons, companies may choose to move, also called to integrate, up or down the supply chain. A move up the supply chain for a certain company involves taking over activities and responsibilities previously carried out by one or more suppliers. A move down the supply chain may involve making products more complete before moving them on to the next step.