How do the sub sites work in SharePoint?Sharepoint Websites exist in a hierarchy. At the top of the hierarchy is a Top-Level website. There can then be multiple sub sites under this top-level website and sub sites under sub sites. The entire structure is then called a site collection.
Administrators can decide who can create sub sites under the top level website. One can see the list of sites and sub sites below the top level site by using the Sites and Workspaces web page. The list shows only one level at a time.