SharePoint Search – How to create a fully functioning Search Center: Part 1

Within Microsoft Office SharePoint Server 2007, there exists the concept of a ‘Search Center’; a type of SharePoint site that can be created to help users find content. As one might expect, this site includes a search box, search page(s) and results page(s). However, unlike other SharePoint sites, a Search Center also includes Search Tabs, much like popular internet search engines, that allow users to narrow their searches. It is from a SharePoint Search Center that users can search for content stored in SharePoint sites, integrated Line Of Business applications (such as SAP) and federated sources (federation requires the SharePoint Infrastructure Updates).

http://blogs.msdn.com/uksharepoint/archive/2009/05/08/sharepoint-search-how-to-create-a-fully-functioning-search-center-part-1.aspx