There are two types of templates available for Windows SharePoint Service 3.0; Server Admin Templates and Site Admin Templates.
Despite the name, Site Admin Templates do not include site
definitions. They are simply a different way of organizing and
displaying existing lists, libraries and web parts for a specific
scenario or use. Normally you would have to install this type of
template on your own, but to make it easy on our customers, we have
pre-installed them in our SharePoint 3.0 environment. When creating a
new site or workspace, simply select the Custom tab to select a Site Admin Template.
However, Server Admin Templates do include site
definitions, and can therefore be used to create a root website. They
also include customized workflows, dashboards and additional
functionality needed to complete different types of processes or roles.
For a list of the different Server Admin Templates available for site
creation, click here.
If you already have an active Windows SharePoint Services 3.0, you can create a new Site or Workspace and select the Application Templates tab to select a Server Admin Template.
To use your own custom Site Template for use when creating new
sites, you simply need to upload your .stp file into the Site Template
Gallery. This can be found under Site Actions > Site Settings. Then
choose Site Templates from the Galleries menu.