There are a few standard types of essays taught in academic English classes and the Compare and Contrast Essay is a popular one. The Compare and Contrast Essay focuses on differentiating two objects, concepts, beliefs, and so forth using a couple of standard structures: Block and Point-by-Point.
Watch this introduction to compare/contrast essays from ESL Lab Miami. The beginning in instruction and the end is an example, you might have to strain a little to see the text on the screen, viewing full-screen version from the original page might be a good idea.
For a great description of block and point-by-point styles, visit ESLbee.com. This site has a great explanation of the compare/contrast essay http://www.eslbee.com/compcont.htm. Pay special attention to their examples provided.
As the latter part of the ESLbee.com page points out, though compare/contrast essays do not have to favor one topic over the other, they often do. These are often used as a type of persuasive essay. Sometimes, this bias is subtle while other times it is quite obvious. When subtle, there is little indication in the introduction or thesis regarding the author's position, but the examples in the body make it clearer. When obvious, the introduction and thesis statement may clearly state the author's position, or it may just be clear from the body examples and tone which position is supported.
Write TWO thesis statements for a compare/contrast essay about Naver (Korean portal) and Yahoo!.
When you finish with the thesis statements, I want you to start thinking more about language of comparing and contrasting. You will likely use comparatives (more, less, -er) and superlatives (most, least, -est). You will also use many other expressions. See this list for example and this example (look at page 2).
On the right is an embedded VoiceThread. If it is too small for you to see, you can go to the original site to see it larger. There are 3 pictures in here. Two are pictures of me and the last is a picture of a question mark. What you are going to do is comment on the three pictures in the ways described below. You can use text, audio, or even video to comment on the pictures, it's your choice.