Adding Content Types
Most libraries are associated with one document template, which determines the default application used to create new files. You add templates by creating new content types for the site, and then adding them to the library. This creates a mixed-type library, which displays more than one application on the New menu, as shown in Figure 5-7.
You may want a mixed-type library if your document-creation process requires multiple types of documents for a specific project. For example, your project management team might need a Statement of Work (.doc), Project Plan (.mpp), Deliverables List (.xls), and executive briefing (.ppt) for each project. By putting the templates for all of the document types in the same library, you can then group the documents by Project using a custom view.

Figure 5-7. Add content types to use multiple document templates within a library
To create a new content type:
Create the documents to use as templates (template.xls, template.doc, etc.) for each Office application you wish to use from the library. Save them in a Templates folder on your desktop.
Navigate to the top-level site and click Site Actions → Site Settings, and then click "Site content types" under the Galleries heading in the middle of the page. SharePoint displays the Site Content Type Gallery page.
Click Create on the toolbar. SharePoint displays the New Site Content Type page.
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