It can be as simple as a “For Sale” card placed on a supermarket noticeboard:

The vendor is giving notice that a product is for sale at a given price to people who might be interested in buying it. This harks back to the earliest forms of advertising, when exotic new goods shipped into Europe from the Far East and India (eg tea and spices) needed to be brought to the attention of people who had never encountered them before.

However, even a supermarket noticeboard might be considered a crowded marketplace as there may be other desks offered for sale, and other advertisements for customers to read. In order to attract a customer's attention to this particular advertisement, the person offering the desk for sale has to make it eyecatching - perhaps through simple use of colour:

They also have to emphasise the benefits of the product they are offering. There are only two basic benefits that a product has when compared to others of a similar sort. It can be described as being better or cheaper (or both!!):

They might also add an image of the desk - a picture is worth 1000 words after all - in order to persuade the consumer still further that this desk is the right desk to buy. They might add a headline or slogan to their ad, to announce exactly what it is that is being sold. Thus they have all the basic elements of print advertising: a catchy slogan, an image, and copy text. This advertisement will hopefully fulfill its purpose which is to provide information which might influence someone to buy the desk. It has done this by linking the vendor of the desk to people who are looking to buy a desk. The link appears in the medium of the supermarket noticeboard, and the vendor pays the owner of the medium to place it there. The vendor has chosen this medium because the kind of people who buy the kind of desk advertised read advertisements on supermarket noticeboards.

Therefore advertising is

• A message from vendor/manufacturer to consumer
• Intended to give information which will influence consumer choice
• Aimed at a known audience
• Paid for