Happiness Bookmark wrote a great article on how to use links effectively. I agree with it, so I decided to write my own suggestions on using links for everyone's reference.
* Internal Links
Internal links generally recommend previous articles that readers might be interested in, which can enhance the relevance of content. They can also help combat plagiarism to some extent, even though some people may remove the links; still, having them is better than not having them at all. My favicon design series has been reprinted many times, and among those who did so, there were people who deliberately concealed the source. However, because there were many illustrations, they didn't have the time to delete each one, so the internal links inside survived. There was also an article on how to build an efficient tagging system for your blog, where I intentionally left a plain-text link (of course, also for the purpose of showcasing the URL), and it too survived in the hands of plagiarists. In such an environment, there isn't any particularly effective way to deal with plagiarism, but don't keep mentioning your own name in the text either—consider the feelings of legitimate readers, please.