This article discusses the main criteria used to classify different types of businesses based on their size. It explains micro, small, medium, and large businesses and their contribution to the industry. Additionally, it defines and describes the features of sole trader, partnership, private limited liability, public limited liability, and cooperative businesses. This content is relevant to the BSC (Hons) Business Management with Foundation course under the Business in Practice module (BMP3002) at the University of Bolton and Regent College London.