Engine is a technical device that converts various types of energy into mechanical work. The most common engines today are internal combustion engines and electric motors. Internal combustion engines are classified according to various characteristics. They are usefully divided into: stationary - these are industrial motors, motors for generators, drilling, compressors and other equipment; Transportation - engines for construction machinery, engines for passenger cars, engines for trucks, engines for agricultural machinery, engines for water transport, engines for air transport. According to the type of fuel, the engines are divided into gasoline, diesel, gas and diesel. All the global engine manufacturers are represented in the Port of Machinery marketplace. The most advertised ads are: sell / buy MAN, Perkins, Renault, Deutz, Caterpillar, Isuzu, Cummins, Komatsu, Yanmar, Mercedes-Benz, Volvo, Iveco.