Demand is generated by need. For basic life people need food, clothes, shelter, a sense of security and belonging. Nevertheless, people are of a social nature and the mechanism of interaction causes them to develop the desire to satisfy their original needs. If they need food, they reach for a bread roll with butter or for caviar; when they need clothes, they buy either a cheap sweatshirt on sale at the hypermarket or a jumper from the latest Versace collection. On top of that, there is a demand for specific products or services backed up by possibilities and the wish to purchase given things.