Please forgive the ignorance of a newbie, but would someone please explain the difference between skins and containers, and how exactly I can add a container to a page, similar to the gradient colored boxes on the default home page after install?

My first understanding (assumption) was that the skin was the overall background picture, and the contaners were insertable "divs" that could be placed on the page. After seeing the 'layout' options, and trying to find a way to insert a container, I no longer think they operate that way.

I would like to be able to place boxes (like the ones on the default home page) onto my pages, or even change the format of any containers that may already be on a page, but selecting a different container in the settings does nothing, and the preview function also does nothing. The skin doesn't change when previewed after selecting a different container. I am using the default ones included in the installation.

If this info is explained in detail somewhere, please point the way to it, and accept my apologies for not being more diligent in finding it. Thank you.