In order to be effective, any advertising must be seen, must be read, must be believed, must be remembered, and must be acted upon. An effective advertisement is one that commands attention, leading to Interest in the product, thence to desire to own or use the product, and finally to action (normally purchase or at least a step towards it, e.g. logging on-line for more information). All commercial communications that weigh on the ultimate objective of a sale must carry a prospect through four levels of understanding. The prospect must first be aware of the existence of a brand or company, they must have a comprehension of what the product is and what it will do for him, they must arrive at a mental suspicion or conviction to buy the product, and finally they must stir themself to action. it is clear that the purpose of marketing communication is to help move a potential customer along a continuum from a state of ignorance towards a position of decision and action.