This question answers itself.
The author's purposelessness
The purpose of an advertisement is to persude consumers to buy a product or service.
to appeal to the readers physical experiences
to entertain the readers
to tailer your appeal to your intended readers
To entertain readers about a adventure/thriller/romance. To inform readers about what could happen if war continues throughout the world.
Answer this question… It allows readers to evaluate a source for themselves.
the pourpous of twilight is to entertain readers. just the same as harry poter/
A newspaper article
To let readers know if a play is worth seeing
provide background to help readers understand the narrative
provide background to help readers understand the narrative