• A submersible pump is one which is submerged in water or any other fluid medium.
• These pumps have an electric motor as the prime mover. The water or fluid moves from the bore well or a submerged tank through a series of stages, a stage comprising an impeller and diffuser/bowl, and is pumped out at the ground level or as per the application need.
• The impeller which is mounted on the shaft spins due to the mechanical energy provided by the prime mover. As water gets sucked into the impeller through the eye, it gains kinetic energy from the impeller vanes. 
• The water exits the impeller vanes and enters into the diffuser/bowl, where the kinetic energy is converted to pressure (head). The water then moves on to the next impeller and Head (Pressure) of water increases at each stage as described above, until it reaches the delivery casing.
• At the delivery casing the water reaches the end application with the necessary accessories.

The submersible pumps can be classified as radial flow, transition flow or mixed flow based on the specific speed of the pump. In general, the mixed flow is meant for higher discharge, whereas radial flow pump operates at higher head with lower discharge.

An electric submersible is one where is the prime is an electric motor. The electric motor can be of any the following types: AC, DC, Brushless DC, PMSM, SynRM. These can be water cooled or oil cooled.

A bore well submersible pump used for clear water application is a centrifugal pump. Typically, these pumps have multiple stages of impeller and diffuser/bowl to build water pressure (head).