The manual combines in one edition the theoretical part of the discipline of the same name and a laboratory workshop. Basic issues of computer organization are considered: computer functional organization, command systems and command cycle. Much attention is paid to the arithmetic foundations of computers, the principles of building various devices and their interaction. The issues of building microprocessor systems are discussed. The laboratory workshop is held on the software model of the computer presented on the attached CD-ROM. The manual also contains materials for performing course design.