Advertising today is a large enterprise. It is both an industry in itself and a tool used by a wide range of people. It represents a very considerable expenditure and so has to be approached carefully and efficiently.

Advertising is widespread because it serves a necessary purpose. In a simpler society, or a smaller economy, or with a small population, relationships might be personal and direct, and there might be no need for anything other than personal dealing from individual to individual. But, in a complex, large, industrialised society, personal dealing needs to be supplemented and reinforced – by communication of an indirect kind and, among other things, by advertising.

Advertising serves a contemporary purpose. It is a purpose dictated by scale, size, distance, convenience and cost. We advertise because it helps us if we do. Advertising is not just a force for commercial organisations and large-scale industry, a tool of them and us. It is a method used across the length and breadth of society, for the following purposes:

- for commercial business, to sell goods and services

- for recruitment, to obtain staff

- by central government, to inform the public

- by local authorities, to announce local services

- for books, or travel, or education courses

- for financial services or for entertainment and leisure activities

- by companies to announce their results or new ventures

- for health care products or services

- by individuals, to buy and sell personal goods

- by political parties, to solicit votes.

The list of advertising usages extends much further. It is continuously widening. All these usages have a common denominator: the need to communicate a message, sometimes commercial, sometimes public service, sometimes for business, sometimes for private purposes. Advertising communicates a message or proposition, which can contain or combine different purposes, of which two are the key characteristics:

1. advertising seeks to inform

2. advertising seeks to persuade.

The emphasis may vary. Pension-increase advertisements may inform more. Beer advertisements may persuade more. But in most advertisements there is a mixture of the two.