To create a hyperlink you first need to activate the text area. This is done by double clicking on the text. You will know that it is properly activated when you see a solid lined box around the paragraph. Next, select the text where you want to have the hyperlink. Then select the hyperlink icon. This will open the form fields where you can add the URL and title of the hyperlink.

Here you can see the hyperlinked words in the green.

To delete a hyperlink start by clicking on it to activate the container. You will know the container has been activated when you see the word 'Link' in the upper left corner. Next, click on the formatting icon (the one just to the left of the trash bin). And that's it. The hyperlink is instantly removed.

Here you can see the deleted hyperlink. The green text is removed.