Deciding on a purpose
Even description for description's sake should have a purpose. Is there an important overall impression you wish to convey? A central theme or general point? This is your thesis; organize your essay around it. For example, you might describe your car as your home away from home, full of snack foods, changes of clothing, old issues of the Chico News & Review , textbooks, and your favorite music. Or, you might describe your car as an immaculate, beautiful, pampered woman on whom you lavish attention and money. Just don't describe your car in cold, clinical detail, front to back (or bottom to top, or inside to outside) without having in mind the purpose, the overall impression you want to create. To achieve this impression, you should not necessarily include all details; use only those that suit your purpose.
Longer essays may also contain an introductory page that defines words and phrases of the essay's topic. Most academic institutions require that all substantial facts, quotations, and other porting material in an essay be referenced in a bibliography or works cited page at the end of the text. This scholarly convention helps others (whether teachers or fellow scholars) to understand the basis of facts and quotations the author uses to support the essay's argument and helps readers evaluate to what extent the argument is supported by evidence, and to evaluate the quality of that evidence. The academic essay tests the student's ability to present their thoughts in an organized way and is designed to test their intellectual capabilities.