Preview Server
Selecting "Preview" as the destination when publishing will publish your content to a preview server. This server is used as a place for pages to exist that others can view/review before being published live on Content Delivery. The content is published to the URL beginning with www.preview.ualberta.ca and the folder structure following will be dependent on your site and the location of the content in your IA.
This server is not indexed by search engines. Content placed here will not appear in search results.