What is the function of the inverter

What is the function of the inverter: the operating voltage and frequency can be changed (usually the output voltage is 0 - 380V frequency 0 - 50Hz). It can simplify the starting and speed regulation of the motor, and can realize automatic control, remote transmission control, automatic pressure, water level control, automatic speed control, especially for the smooth start of large machinery, automatic control of deep water wells, etc.