Suppressing the Salesforce User Interface and Styles

By default, Visualforce pages adopt the same visual styling and user interface “chrome” as the rest of Salesforce. This default styling behavior lets you create pages that look like they’re built right into Salesforce. If you don’t want a page to have the Salesforce look and feel, you can suppress various aspects of the Salesforce page and visual design.
You can change the page-level user interface resources added by Visualforce using the following attributes on the <apex:page> component.