An essay is a short piece of writing that discusses, describes or analyses a topic. It can discuss a subject directly or indirectly, seriously or humorously. It can describe personal opinions, or just report information. An essay can be written from any perspective, but are most commonly written in the first person (I), or third person (subjects that can be substituted with the he, she, it, or they pronouns). There are many different kinds of essays. The following are some of the most common ones:

The function of the expository essay is to explain something to the reader by giving directions or instructions, or to acquaint your reader with knowledge about how to complete a task or how something is done. You are demonstrating your own knowledge and explaining with facts, not your opinion. It is very important that your tone be reasonable and that your presentation be factual and believable.
Compare and Contrast
The essay could be an unbiased discussion, or an attempt to convince the reader of the benefits of one thing, person, or concept. It could also be written simply to entertain the reader, or to arrive at an insight into human nature. The essay could discuss both similarities and differences, or it could just focus on one or the other. A comparison essay usually discusses the similarities between two things, while the contrast essay discusses the differences.
Cause and Effect
The cause/effect essay explains why or how some event happened, and what resulted from the event. This essay is a study of the relationship between two or more events or experiences. The essay could discuss both causes and effects, or it could simply address one or the other. A cause essay usually discusses the reasons why something happened. An effect essay discusses what happens after a specific event or circumstance. Sources are often required in a cause/effect paper, and your choice of these sources is important as they reflect on the validity of your argument.

Argumentative (Persuasive)
An argumentative essay is one that attempts to persuade the reader to the writer’s point of view. The writer can either be serious or funny, but always tries to convince the reader of the validity of his or her opinion. The essay may argue openly, or it may attempt to subtly persuade the reader by using irony or sarcasm. Your approach is to take a stand on an issue and use evidence to back up your stance, not to explore an unresolved topic.

You must choose a side, make a case for it, consider and refute alternative arguments, and prove to the undecided reader that the opinion it presents is the best one. You must be aware of other sides and be fair to them; dismissing them completely will weaken your own argument. It is best to take a side that you believe in, preferably with the most supporting evidence. It can often be educational to adopt a different position from what you might normally choose (debating requires this kind of flexibility).

Written mainly for enjoyment. This is not to say that it cannot be informative or persuasive; however, it is less a formal statement than a relaxed expression of opinion, observation, humour or pleasure. A good informal essay has a relaxed style but retains a strong structure, though that structure may be less rigid than in a formal paper.

The informal essay tends to be more personal than the formal, even though both may express subjective opinions. In a formal essay the writer is a silent presence behind the words, while in an informal essay the writer is speaking directly to the reader in a conversational style. If you are writing informally, try to maintain a sense of your own personality. Do not worry about sounding
academic, but avoid sloppiness.

Critical Review
This type of essay can be either formal or informal, depending on the context. Its goal is to evaluate a work such as an article or book. Your personal, informed, opinion plays a significant role in the process. However, a certain objective standard needs to be maintained and, as in an argumentative essay, your assertions need to be proved.

The formality of the review will be determined by how much of the essay is analysis, how much is summary and how much is your reaction to the work you are reviewing. A more formal review will not only discuss the work on its own merits but also place it in  context. Newspapers and popular magazines often review in terms of finance: is this CD or film worth spending your money on? Critical journals will attempt to determine whether a new novel or play has achieved something new and significant. A good review will discuss both the qualities and the importance of a given work.

Research (Analytical)
The research essay leads you into the works of others and asks you to compare their thoughts with your own. Writing a research paper involves going to source material  and synthesizing what you learn from it with your own ideas. You must find texts on the subject and use them to support the topic you have been given to explore. Because it is easy to become lost in a wilderness of source material, you must take particular care to narrow your topic. A research paper should demonstrate what you have learned, but it should also show that you have a perspective of your own on the subject.

The greatest danger inherent in the research essay is plagiarism. If your paper consists of a string of quotations or paraphrases with little input of your own, you are not synthesizing but copying, and you should expect a low grade. If any of the borrowings are unacknowledged, you are plagiarizing, and the penalties can be severe.

In the literary essay, you are exploring the meaning and construction of a piece of literature. This task is more complicated than reviewing, though the two are similarly evaluative. In a review you are discussing the overall effect and validity of written work, while in a literary essay you are paying more attention to specifics. A literary essay focuses on such elements as structure, character, theme, style, tone and subtext. You are taking a piece of writing and trying to discover how and why it is put together the way it is. You must adopt a viewpoint on the work in question and show how the details of the work support your viewpoint.

A literary essay may be your own interpretation, based only on your reading of the piece, or it may be a mixture of your opinions and references to the criticism of others, much like a research paper. Again, be wary of plagiarism and of letting the opinions and ‘voices’ of more experienced writers swamp your own response to the work. If you are going to consult the critics, you should reread the literary work you are discussing and make some notes on it based on your own viewpoint before looking at any criticism.

• Title (sometimes followed by an introduction)
• Thesis statement, body and conclusion
• Appropriate paragraphing with main ideas
• Supporting details and examples
• Organization of ideas
• Maintaining coherence - using cohesive devices (such as pronouns, linkers)
• Presenting ideas without digression