The thesis and conclusion elements of a paper work together to express your point of view. In your paragraphs between your thesis and conclusion, you should aim to encourage the readers to think about an issue in a slightly different way than they did before. A well-researched paper is the best way to convince readers that your ideas are valid. A good conclusion reminds the readers what they gained by taking the time to read your paper, even if they don't agree with you.
When you raise multiple points in an essay or paper, there's a good chance that your reader won't retain all of them. One of the purposes of your conclusion should be to round up your ideas as you close your paper. Instead of simply repeating ideas from your paper, however, you should synthesize them. For example if your paper is about types of apples, your conclusion should talk about the significance of apples without rehashing or rewording facts in your paper.
Your thesis statement tells the readers what to expect as they read through your paper. Your conclusion can give the reader additional insight by writing about how you found your point of view through your research. For example, you believed that there were only two kinds of green apples before you wrote your paper, but found out about many more types through your research; this can be worth mentioning in your conclusion. Be careful to limit your insight to information that's included in the body of your paper. Don't bring up new information in your conclusion that you didn't address in your paper.
Ideally your paper helped your readers learn something they didn't know before, and a good conclusion invites them to take action using the information they just learned. For example, your conclusion may ask your readers shop, vote, or simply think differently about apple-related issues after reading your paper. Close with a statement about the broader implications of what could happen if more people shared the points of view expressed in your paper.