HTML Server Controls

HTML Server Controls map to their corresponding HTML tags and simply output the HTML tags at run time. HTML elements in ASP.NET files are, by default, treated as text. To make these elements programmable, add a runat="server" attribute to the HTML element. This attribute indicates that the element should be treated as a server control.

If there's an HTML server control that corresponds to the HTML tag you've "contol-ized," the HTML tag becomes the corresponding type of server control. Otherwise it will simply default to an HTML control of type HtmlGenericControl.