In the previous exercises, you created an ASP.NET page and added Web Part zones and Web Parts to it, but it did not contain any SharePoint site navigation nor did it inherit any look and feel from the SharePoint site. You can envisage the page we created as just the content page. It is not associated with a master page, which is the page that defines the common user interface and code.
In this exercise, you will attach a master page to an existing page.
USE the SharePoint team site you modified in the previous exercise.
OPEN the site in SharePoint Designer, if it is not already open, and display the ParcelDelivery.aspx page.
On the Format menu, point to Master Page, and then click Attach Master Page.
The Select A Master ...