On the Moodle site, you can show other content from anywhere on the Web by using a link. You can also link to files that you've uploaded into your course. By default, this content appears in a frame within your course. You can also choose to display it in a new window.

When using content from outside sites, you need to consider the legality and reliability of using the link. Is it legal to display the material within a window on your Moodle site? Will the material still be there when your course is running? In this example, I've linked to an online resource from the BBC, which is a fairly reliable source:

Remember that the bottom of the window displays Window Settings, so you can choose to display this resource in its own window. You can also set the size of the window. You may want to make it appear in a smaller window so that it does not completely obscure the window with your Moodle site. This will make it clearer to the student that he or she has opened a new window.