FRICTION is a phenomenon that is part of our daily lives - in one sense we would find most difficult to survive without it yet in another it can be most expensive to minimise.
It can be simply identified as the resisting force that arises when one surface slides, or tries to slide, over another. It is commonly the textural property measured from packaging materials, shaving gels, cosmetic sponges, etc.
Friction can be a limitation to us; for example, the friction of packaging can be a major limiting factor in the speed of packing machines. Additives are often used to improve the lubricity of surfaces, this is known as 'slip'. Polythene is added to packaging to improve slip characteristics.