Unit 5 included information on how to use positioning within your web page. Here are some examples.
I am using absolute positioning for this image.RED.
Now I'll use relative positioning with the same image, same top and left specifications. GREEN.
Relative positioning places the image to the specified top and left settings relative to it's own position within the normal flow of the page.
It's position is affected by anything else on the page
Absolute positioning places the image relative to the top-left corner of the browser window,regardless of other images, etc.