What Are Master Pages?
Master Pages in ASP.NET are one more way to provide consistent look of your web site. In content page you define only content that is specific to that page. In Master page goes all content common for complete site, like menus, header, footer etc.
When web browser requests a web page, server will merge content page and master page and return combined output.
Master Pages have .master extension and must have Master directive, like this:
[ C# ]
<%@ Master Language="C#" AutoEventWireup="true" CodeFile="MasterPage.master.cs" Inherits="MasterPage" %>
[ VB.NET ]
<%@ Master Language="VB" AutoEventWireup="true" CodeFile="MasterPage.master.vb" Inherits="MasterPage" %>
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