An essay, by definition, is a written piece that offers the author’s opinion, usually in support of some opinion or point of view, but often the definition is highly vague, encompassing all manner of literature, a newspaper, a book, an essay, and even a short story. Essays have historically been categorized either formal or informal. Formal essays are written for any purpose that requires an argument, usually for college admission or for publication. In these instances, the essay writer is required to follow specific guidelines set forth by the university. Informal essays are written for amusement purposes only.

The two most common categories of essay are persuasive and academic. A persuasive essay is one that attempts to prove its point of view, while an academic essay is one that is designed to express an opinion, usually about a particular topic and may contain personal opinions or criticism of someone or something. Because they are not arguments in any way, essays on either side of the spectrum share certain basic characteristics.

The most common type of essay is the polemic. Polemic essay is written to defend or oppose a particular view. Often the essayist will present some facts about their side of the argument, usually from a scientific, technological, historical, economical, or cultural point of view. They will use personal experience and anecdotal evidence to bolster their position.

The second most common type of essay, which resembles a more condensed version of the polemic, is the expository essay. An expository essay has the purpose of proving some general claim or doctrine about a particular subject. Usually the thesis statement of this type is a very brief one; it may comprise just a single sentence or a couple of sentences. However, expository essays must include body paragraphs that detail a bit more about each of the main arguments.

Another common type of essay–and one that a lot of students overlook as important–is the narrative essay. A narrative essay deals with the telling of a story, rather than the argument. Some good examples of this kind of essay are persuasive essays, history-based essays, or studies about a single event or trend. Narrative essays are not particularly complex, but they do take some time to develop. In fact, most narrative essays end up as simply a personal story, told from start to finish.

The third most common type of essay, also among the three types described above, is the informational essay. Informative essays are written to offer information about a specific topic. An informational essay can be written to answer a question, provide research information, serve as an advice or counseling piece, or as a background for a particular argument. Unlike expository or descriptive essays, informational essays must contain direct information about the topic at hand. In addition, they must be written in a way that persuades the reader by presenting knowledge in a simple, easy-to-follow manner.