Intentionality - "is at the heart of knowing. We live in meaning, and we live 'towards,' oriented to experience. Consequently there is an intentional structure in textuality and expression, in self-knowledge and in knowledge of others. This intentionality is also a distance: consciousness is not identical with its objects, but is intended consciousness" (quoted from Dr. John Lye's website - see suggested resources below).
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.