DC motors are one of the most common types of electric motors, including single pole motors and electromagnetic DC motors. A unipolar motor has two magnetic poles, which cut off the unidirectional magnetic field lines of the magnetic flux by rotating the conductor around the axis of rotation, thereby creating a stable magnetic field. Electromagnetic DC motors are composed of stator magnetic poles, rotor (armature), commutator (commonly known as rectifier), brushes, housing, bearings, etc. According to different excitation methods, they can be divided into series excited, parallel excited, separately excited, and compound excited DC motors. ‌

AC motors, especially asynchronous motors, are another common type of electric motor. It is powered by an AC power source and uses changes in magnetic field to drive the rotor to rotate. ‌

Hydraulic motors and pneumatic motors are devices that convert the pressure energy of liquids or gases into mechanical energy. Hydraulic motors are mainly used in applications that require high torque and heavy loads, such as construction machinery, building machinery, etc. Pneumatic motors are commonly used in applications that require high power density and small volume, such as stirring, dispersing, or transporting paints and coatings.