A food cooperative or food co-op is a grocery store organized as a cooperative. Food cooperatives are usually consumers' cooperatives and are owned by their members. Food cooperatives follow the 7 Cooperative Principles. The cooperative movement started in the 1840s and the first notable food cooperative was in Rochdale, England, started by industrial weavers. The cooperative movement saw a resurgence in the United States in the 1970s when many "second wave" cooperatives started. The National Cooperative Grocers Association (NCGA) is a cooperative federation in the United States that is composed of 108 food cooperatives.