There is a way to create hidden content in the admin interface: go to the "my account" tab and check the two parameters on the bottom of the left-hand column. You will then have a new box at the bottom of the content edit page where you can set visibility of the newly created node.
Principal Consultant International Business
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The "Content structure" tab allows the user to browse and manage the nodes that belong to the "Content" top level node. This is the part that makes up the actual structure of the site. It may contain menu items, folders, articles, comments, products, forum messages and so on. The following screenshot shows what the administration interface displays when the "Content structure" tab is selected.
