Best Practices for Static Resources

Displaying the Content of a Static Resource with the action Attribute on <apex:page>
You can use the action attribute on a <apex:page> component to redirect from a Visualforce page to a static resource. This functionality allows you to add rich, custom help to your Visualforce pages. For example, to redirect a user to a PDF:
  1. Upload the PDF as a static resource named customhelp.
  2. Create the following page:
    <apex:page sidebar="false" showHeader="false" standardStylesheets="false" 
          action="{!URLFOR($Resource.customhelp)}">
    </apex:page>
Notice that the static resource reference is wrapped in a URLFOR function. Without that, the page does not redirect properly.
This redirect is not limited to PDF files. You can also redirect a page to the content of any static resource. For example, you can create a static resource that includes an entire help system composed of many HTML files mixed with JavaScript, images, and other multimedia files. As long as there is a single entry point, the redirect works. For example:
  1. Create a zip file that includes your help content.
  2. Upload the zip file as a static resource named customhelpsystem.
  3. Create the following page:
    <apex:page sidebar="false" showHeader="false" standardStylesheets="false" 
          action="{!URLFOR($Resource.customhelpsystem, 'index.htm')}">
    </apex:page>
When a user visits the page, the index.htm file in the static resource displays.