The term advertising indicates the set of communication techniques used to sell goods or services. Over the years, advertising has gone from being something similar to gambling, - it could go well, or it could go wrong, just like when you place a bet - to being one of the safest and most profitable entrepreneurial endeavours:as long as it is done according to a certain set of rules. This change was made possible by comparing and testing the results of thousands of advertising campaigns worked on by a number of large agencies. The agencies involved continue to be the custodians of the most detailed knowledge of this field because, despite the changing of teams over the years, they have kept copies of all of the advertising campaigns that have been carried out, and their results, both positive and negative. Therefore, in the advertising field, we started to see the emergence of what, in the scientific field, is called "literature", that is, a series of cases from which to draw lessons and then, once consolidated in practice, new principles on which to base an advertising strategy.
Having fundamental principles on which to base one's advertising strategy allows the individual professionals involved not to have to start from scratch every time, but to navigate routes already traced by those who have trodden that path before them. This saves time and money, and guarantees success. Today, in fact, if an advertising company goes under - which is still possible - it is because it has not taken the cornerstones of advertising into account.
To draw up these rules, the public response to advertising was studied. The main sector that this data was drawn from was that of mail order, as in this area, everything is tracked: from the cost per response to the presale cost, from the marketing levers used to the creative devices involved, and even the general parametres set for each individual advertising campaign. Furthermore, in mail order sales, it is also very easy to compare two different advertising strategies.