An essay is a piece of writing several paragraphs long. It is about one topic, just as a paragraph is. However, because the topic of an essay is too complex to discuss in one paragraph, you need to divide it into several paragraphs, one for each major point. Then you need to tie the paragraphs together by adding an introduction and a conclusion.
Writing an essay is no more difficult than writing a paragraph except that an essay is longer. The principles of organization are the same for both, so if you can write a good paragraph, you can write a good essay.
An academic essay has three distinct sections – the introduction, body and conclusion:
An essay introduction consists of two parts: a few general statements to attract your readers’ attention and a thesis statement to state the main idea of the essay. A thesis statement for an essay is like a topic sentence for a paragraph: It names the specific topic and gives the reader a general idea of the contents of the essay. The body consists of one or more paragraphs.
Each paragraph develops a subdivision of the topic, so the number of paragraphs in the body will vary with the number of subdivisions or subtopics. The conclusion, like the concluding sentence in a paragraph, is a summary or review of the main points discussed in the body.
An essay has unity and coherence, just as a paragraph does. Transition signals and the repetition of key nouns link the paragraphs into a cohesive whole.