Yet another type of input is HIDDEN input.

<INPUT TYPE=HIDDEN NAME="FORMNAME" VALUE="Friend Form 1">

A HIDDEN input is a value/name pair which is returned to you but doesn't show up anywhere on web page. The hidden input above is required for use with mailto Formatter (MTF). It's how MTF recognizes the forms it has to parse.

Assume you were a company trying to generate leads for a new product and there is a standard form for gathering information which has name, company, products, phone interested in, etc. Only problem is there are 6 slightly different versions of form in 6 different places. You need to know what's coming from where. What to do?

You can add a HIDDEN input to your forms like below:

<HTML>

<BODY>

<FORM METHOD=POST>

<INPUT TYPE=HIDDEN NAME="FORMNAME" VALUE="Version 1"> ...for the first version

<INPUT TYPE=HIDDEN NAME="FORMNAME" VALUE="Version 2"> ...for the second version

<INPUT TYPE=HIDDEN NAME="FORMNAME" VALUE="Version 3"> ...for the third version

</FORM>

</HTML>

By the way, it doesn't matter what name/value pair in the hidden input is (or any input for that matter).

<INPUT TYPE=HIDDEN NAME="E" VALUE="Mc^2">HIDDEN

Inputs are also useful for cgi scripts. For instance, many ISP's have a script you can have your forms sent to. It then sends form back to you properly formatted. Hidden input can be used to tell cgi script who you are, where to send parsed data and so on.