The rules of writing a compare and contrast essay
A common format for essays is a comparison of two things, often known as a compare and contrast essay. The two things can be almost anything; two films, for example, or two types of scenery - deserts and jungles, perhaps. No matter what they are, though, there are some simple rules that you should follow when writing this type of essay.
All essays should start with an introduction. In this case its purpose is to let the reader know what you'll be comparing, but don't start any descriptions of them just yet. Instead put in something to get the reader's attention. Ideally it should lead on to the next part, the thesis.
Most essays need a thesis. This is the central idea that the essay discusses. If you're comparing jungles and deserts the thesis could be that they're both equally valuable as habitats for animals.
The main part of the essay is the body. This is where you present arguments for and against the thesis, with the aim of steering the reader towards a conclusion. In a compare and contrast essay the structure of the body is more complicated than usual, because you have to discuss two separate things. It's easy to get it wrong and end up with a muddled body that doesn't lead to a conclusion, but that can be avoided. There are two different structures you can use.
First there's the two-block structure. To do it this way, split the body into two sections. Each section deals with one of the things you're comparing. The first one should be purely descriptive; this sets the scene and builds up a clear picture for the reader, that you can base comparisons on in the second section. When writing the second one you need to include both descriptions of the second topic and comparisons with the first. Each section should be laid out in the same order; if the topics are films, for example, you could begin by describing the characters, then the plot and finally the special effects, but it's important to do it the same way each time. That reduces the chances of confusion.
The other method is the point by point structure. In this you alternate between the two topics. For film you'd start by discussing and comparing the characters in both films, then the plots and then the effects.
Finally, write your conclusion. Your readers might not all agree with this, but they should at least be able to agree that it's a valid one. There shouldn't be anything discussed in here that wasn't mentioned in the body or that contradicts what you wrote there. However it's fine to argue that points from the body, while true, aren't that important.
As long as you structure it properly a compare and contrast essay can be very informative, and also very easy to write. Just do some planning before you start, work out what structure you want to use and stick to it. Interesting writing guides may also be found here.