Most academic pieces of writing have the structure introduction, development or body of your paper and conclusion.  An academic paper follows this basic structure as well.

It may well be that the topic you have to write about has been given to you and, therefore, you may or may not be very keen on it, or else you may have chosen it for a particular reason.  In any case, before starting to write an academic paper it is always worth spending a few minutes thinking about the topic.

The introduction is the opening paragraph in a paper. As the name indicates, the introduction presents the topic you will be discussing in the development of you paper.  In fact, the introduction starts creating the right atmosphere for the reader to understand the ideas you will put forward in your paper later on.  It’s like welcoming a guest home before a good meal.  Your guest can get tips of what the meal will be like from hints you give him (introduction), but he will still have to wait to be served to taste the meal (development) and see if it bears any resemblance with the hints given.

Thus, the introduction should let the reader know what the topic is about but should also be narrowed down and set certain limits. The introduction cannot be too general or too detailed.   If it is too general there will be many ideas that will probably not be directly related to the topic and therefore will not be relevant. In fact, it will give a very poor impression of the writer as it may suggest that he has not understood the topic or else -what is even worse- that is waffling in an attempt to reach a certain number of words.    On the contrary, if the introduction is too specific then there will not much to write about, because it will be too precise, so the ideas cannot be developed.

In the introduction you should let the reader know what the topic is about but you should also narrow it down and set certain limits to it.

At the end of your introduction, you should also put forward a claim or a thesis statement that will be considered in later paragraphs.  This last sentence should also indicate the reader which course of argumentation you will take in the rest of the paper.

It is important that you include a claim as this will help organize the structure of your paper.

The number of paragraphs you write in the introduction depends on framing the topic and also on the length of the paper, if you have to write a certain number of words.  As a general rule the introduction should never be longer than the development of your paper, since the development is one of the most important parts in your paper.

If you need to write several paragraphs in the introduction, make sure that they are really necessary. It could be the case that you have not defined your area of research well.  If you need to write several paragraphs they should have a similar length.  That’s to say, there should not be one paragraph that is unnecessarily much longer than other paragraphs.  If that is the case, that paragraph can probably be divided into two or even three paragraphs.  All paragraphs should have more or less the same length.

The development is that section in your paper where you will be putting forward your arguments to develop and support the claim that you wrote at the end of your introduction.  As the introduction is the core of your paper it is important that you have enough arguments to write paragraphs that support your general claim.

The number of paragraphs that you write depends on the number of points you try to make but each paragraph should have a topic sentence or an assertion that relates directly to the claim you have made.  This assertion should be backed by supporting sentences that help explain your ideas in full.  Each paragraph should come to some kind of conclusion that also marks the transition into a new paragraph.  These transitions should as smooth as possible and should let the reader go smoothly from one idea in one paragraph to another idea in the next paragraph.

In the conclusion you restate your main claim/s.  Some academics suggest the main claim should be reinforced rather than restated.    You should also explain why your claim is important and what derives from it.