The course is concerned with the application of fundamental physical laws, above all hydromechanics and thermo-mechanics for the design and utilization of a large group of machines. The basic principle of these machines is transformation of thermal, pressure or potential energy into kinetic energy of fluid and the transfer of that energy to the rotor of the machine, and vice versa. Therefore, substantial parts of the course are focused on compressible fluid with high velocity and interactions between a real fluid flowing around or through bodies. Due to the high speed, relatively small machines reach high power outputs. Turbo-machines are used in a great number of applications and in a very extensive range of working conditions. The explanation on physical principles is accompanied with the design of turbo-machines.