In the U.S., credit unions have a clear organizational structure. All credit unions belong to one or the other parent credit union (there are 35 of them in the U.S.). Corporate credit unions are united on a cooperative basis in the Central Credit Union (US Central Credit Union). In the UK, credit unions are a source of financing of people groups. This tool is not widely used. Credit unions historically formed as a special form of social support, initially taken upon themselves the social mission of protecting the interests of citizens in the field of financial services.