This final paper describes busbars, their role and application. Their operation under normal operating conditions and under short circuit conditions is analyzed. The second chapter presents the method of manufacturing busbars and the materials used in their manufacture. It also discusses the properties of aluminum and copper conductors and their alloys. The role of insulators in electrical installations and the method of their construction and installation is also described. In normal operation, the cross-section of busbars is selected according to the maximum current flowing through the most loaded part of the busbars. This current is determined by the thermal load. The negative effects of temperature increase and the selection of busbar cross-sections are described in the third chapter. The fourth chapter presents the thermal loads of busbars during a short circuit, the calculation of the required cross-sections and temperature increases. The negative effects of electric arcs and pipe expansion are also described. The last chapter presents the mechanical characteristics of busbars during a short circuit and the forces that destructively affect them. The stresses of busbars in their standard design are analyzed.