server controls are html elements / control that possess the runat="server" attribute as you can see in the real world example below. asp.net reads html elements within an asp.net page as literal text if they do not have this attribute . in case you want to reference the control from code you must give it an ID.

<asp:HyperLink ID="HyperLink1" runat="server" NavigateUrl="~/ContactUs.aspx">contacting
us</asp:HyperLink>