Gases and liquids are collectively known as fluids. Fluid friction is a force that restricts the movement through the fluid.
The factors on which fluid friction depends are as follows:
1) Speed of the body:
Speed and friction are directly proportional to each other. For instance, a body moving with higher speed will experience more drag than a body moving with comparatively lesser speed.
2) Nature of the fluid:
The thinner the fluid, the lesser the fluid friction will be, and vice versa. For instance, the molecules of water are less close to each other than those of honey. That is why there is less fluid friction in water than honey.
3) Shape of the body:
Streamlined shape of a body helps it to cut through the fluid more easily.