The Hidden Field has many uses on a Web form. It can be used to provide data to the Database, Email Recipient, or Process which the user does not or should not see.

Consider a sceenario where the user will be redirected to an affiliate web site after the Form Submission. A requirement of course in these cases is an Affiliate ID in the URL Querysting. Using the Hidden Field, an Affiliate ID can be added to the form which the user will not see. When setting up this field, make sure that Querystring Parameter name is what is expected by the Affiliate and mark this field to be sent by Url in the Send Value By Options of the Input Control Page. In this scenario, it is also nessecary to make sure the form redirects after submission in the Settings > Other Settings page. It is also commong to exclude Hidden Fields used in this way from being stored or sent in the email using the Exclude from Email & Data option as shown below.

Hidden Field Screen Capture