Internal links are an essential part of Search Engine optimization. It is the process of linking to your own articles wherever it is relevant. When you write a specific article, there could be other relevant articles that might have better and elaborate information on a specific activity or, a specific term. You can link these terms/keywords to those articles thereby providing better information to your visitors and readers. Creating internal links involves identifying such articles and then linking to them using these specific keywords. This can be done manually which takes a lot of time and effort or, by using a plugin like Link whisper which simplifies the entire process.