The exit button
The exit button immediately exits the site and takes you to a Google search page. It’s a quick escape from the site that you may need if someone walks in that you'd rather not see what you're looking at.
If you are in an abusive relationship, and the person abusing you walks in, you can press this button as a fast way to navigate away from the site.
If you are using an up-to-date web browser, then the exit button should move down the page as you read, so it should always be visible to you as you scroll down. If you are using an older internet browser then the exit button will remain at the top of the page and you will need to scroll back up to access the exit button.
Alternatively, you can easily and quickly close the browser window by using the following key short-cuts
Windows PC: Control-W