A narrative hook (or hook) is a literary technique in the opening of a story that “hooks” the reader’s attention so that he or she will keep on reading. The “opening” may consist of several paragraphs for a short story, or several pages for a novel, but ideally it is the opening sentence.

in advertising…

AIDA is an acronym used in marketing and advertising that describes a common list of events that may occur when a consumer engages with an advertisement.

• A – attention (awareness): attract the attention of the customer.
• I – interest of the customer.
• D – desire: convince customers that they want and desire the product or service and that it will satisfy their needs.
• A – action: lead customers towards taking action and/or purchasing.

Using a system like this gives one a general understanding of how to target a market effectively. Moving from step to step, one loses some percent of prospects.

source: wikipedia