The submitted publication focuses on an explanation of the basic terms of commercial law related to business, characteristics of entrepreneurs, enterprise and its organizational part in Slovakia. It also covers issues of position of foreign business entities as well as the forms and possibilities of their business activities. It also analyses fundamental questions related to business name and its protection, trade secret and basic questions of competition law. Special attention is paid to general provisions covering companies and co-operatives that represent an essential and substantial part of legal entities performing business activity. In addition to that, basic common features and differences as well as essentials needed for the foundation and incorporation of companies and co-operatives are dealt with. Individual types of companies are analysed with regards to the rights and duties of partners and shareholders as well as the regulation focused on statutory bodies and questions of liability for damage caused by exercise of function. A separate explanation is dedicated to the processes of merger and de-merger of companies and question of the effects of these on the rights and obligations of shareholders. The textbook is mainly intended for use by foreign students and individuals seeking to acquire legal English terminology. It can also serve as a basic guide and provide help to foreign entrepreneurs.