A parent company, sometimes called a holding company, is a corporation that has subsidiaries, which are wholly or partially-owned separate businesses controlled by the parent.
Although corporate law varies from one country to another, a parent company usually must have at least 50% of a subsidiary's voting stock for control of operations and management. A wholly-owned subsidiary is one in which the parent owns 100% of the stock.
Parent companies with subsidiaries are one type of conglomerate, which is a company comprising multiple different businesses. Holding companies, which exist to own subsidiaries but do not have their own business ventures, are one type of parent company.