CMS code to extract page text to external site

Is there a walkthrough or tutorial to show how I can setup WordPress for a client to allow them to edit private pages on a wordpress, and the text and images they enter will appear on an external website that I have designed for them?
From reading some tutorials it seem it would be better for me to have this based on pages rather than on the Blogs, is this correct?
I have the site already set up, I just need to be able to allow them access to the WordPress as editor – edit the pages on there and somehow encode the existing HTML pages on the site I have set up for them to show the content of what they place on the WordPress Pages.