The first habit in Stephen Covey’s Seven Habits of Highly Effective People is “to begin with the end in mind.” In the case of an essay or paper, our end is a composition consisting of three parts: an introductory paragraph, body paragraphs and a concluding paragraph. (See the University of Virginia’s “Basic Essay Format” https://www.uvu.edu/writingcenter/docs/handouts/basicessayformat.pdf for an excellent overview.)
Our paper will always have an introductory paragraph and a concluding paragraph, but the number of body paragraphs may vary. The “Five-Paragraph Essay,” a popular format for essays and short papers, has three body paragraphs along with an introduction and conclusion. Each paragraph type: introduction, body and conclusion, has a different role.