When you click on a link on a website, sometimes it opens a new window or tab to show you something else. This is useful, but it can also be a security risk because the new window can control the original window that opened it. To prevent this, web developers can add a special code called "noopener" to the link, which stops the new window from being able to control the original window. It's like putting up a fence between the two windows to keep them separate and safe from each other.