Electricity is just like water flowing threw a pipe.Voltage pushes current (or Amps)voltage and current are acting against resistance (or ohms) resistance must be over come to get the work done (like turning an electric motor) In a signal Phase circuit It has 110 volts. In a 2 phase circuit it has 220 volts.But in a 3 phase circuit you have 110 volts on each leg (or input to the motor) there are also 2 different ways to make it work Y-wond & Delta wond. A 3 phase motor has a continious rotating magnetic feild. Separated at 90 degrees.
The most important class of three-phase load is the electric motor A three phase induction motor has a simple design, inherently high starting torque, and high efficiency.(due to incoming the voltage available) Such motors are applied in industry for pumps, fans, blowers, compressors, conveyor drives, and many other kinds of motor-driven equipment. A three-phase motor will be more compact and less costly than a single-phase motor of the same voltage class and rating; and single-phase AC motors above 10 HP (7.5 kW) are uncommon. Three phase motors will also vibrate less and hence last longer than single phase motor of the same power used under the same conditions.