<input type="hidden"/> or
<input type="hidden" />
Creates a control that does not display in the browser. Hidden controls can be used to pass special form-processing information to the server that the user cannot see or alter.
This is an empty element. In HTML, the end tag is forbidden. In XHTML, the element must be closed with a trailing slash as just shown. Developers may include a space character before the slash for backward compatibility with older browsers.
<input type="hidden" name="productID" value="12-XL">
hidden input type is a non-rendering element.