When using ASP.NET, the ASP.NET Server interprets special tags known as ASP.NET WebServer Controls. These ASP.NET WebServer Controls like HTML Server Controls are interpreted at the Server end thus a runat=”server” tag is necessary. ASP.NET WebServer Controls also do not map to any current HTML elements and they also may represent more complex elements.
The following is a code snippet on how to Create a Web Server Control in ASP.NET.
<asp:control_name id=”some_id” runat=”server” />
ASP.NET Web Server Controls