A propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the airfoil-shaped blade, and a fluid is accelerated behind the blade. Propeller dynamics, like those of aircraft wings, can be modelled by Bernoulli's principle and Newton's third law. Most marine propellers are screw propellers with fixed helical blades rotating around a horizontal axis or propeller shaft.
The point of attachment of the blades with the ship propeller boss or hub is called the root. Tip is the furthest point of the propeller blade from the root and tapers like a leaf. It has the least section width. It joins the leading and trailing edges as well as remains the same for the face and the back.