You will find different links that relate directly to the course you are taking. Those links may lead you to articles, podcasts, videos and websites, each of which will either open in a new web browser window or, in the case of articles, sometimes have an option to open within the window as a preview. The following link is an example of a website link that you may see in your course.
Link: Center for Action and Contemplation (Website)
To close the link that opens in a new web browser, simply close that window by clicking on that specific tab's "x". To close an article that opens in your current browser, simply click on the word "minimize" at the top of the article.