What do you mean by fluid friction? How can fluid friction be reduced?

The gases and liquids are called fluid. All of them exert force of friction on solid bodies moving in either of them. The force exerted by fluid is called drag. It depends on speed of the object with respect to fluid. It also depends on the shape of an object and nature of the fluid, is obvious that when objects move through fluids, they have to overcome friction acting on them.

In process they lose energy. Efforts are, therefore, made to reduce friction. So, the objects are given special shapes Birds and fishes move in fluid all the time. Their bodies must have evolved to shapes which would make them lose less energy in overcoming friction. Such shapes are called streamlined This is why shapes of Aeroplan, ships and all vehicles are designed to have shapes which minimize fluid friction.