Master Page Galleries
When you provision a site collection in Office SharePoint Server 2007, the system creates a master page gallery that contains all the master pages and page layouts for that site collection. If the site collection uses either the Publishing Portal or Collaboration Portal templates, the master page gallery includes several master pages that are provided with Office SharePoint Server 2007, such as BlueBand.master. These master pages are located in the path C:\Program%20Files\Common%20Files\Microsoft%20Shared\web%20server%20extensions\12\TEMPLATE\FEATURES\PublishingLayouts\MasterPages\, with other example .master pages. You can use any of these master pages as they are, or you can customize them fully to create unique branding for your site.
Why Start with a Minimal Master Page
Creating and completing a master page to begin your SharePoint site customization takes planning and time. If you can, you want to prevent having to rewrite or back out code you don't need in your master page. This topic shows you how to create a minimal master page that includes only the minimal functionality that Office SharePoint Server 2007 requires so that you have a stable platform upon which to build your own master pages. Creating a minimal master page can help you avoid the time-consuming process of backing code out of a pre-existing .master page such as BlueBand.master, or removing functionality and then building it back in when your customization needs change again.