That's an interesting question.
An HTML form is displayed in a browser. If the form is on disk, that's fine, the operating system should start the user's browser to display the form.
The user can submit the form, but where does it get submitted to?
It gets submitted to the URL in the "action" attribute of the HTML "form" tag.
If that URL starts with "http://" (such as "http://www.yoursite.com/formmail.php") then the form will be submitted across the internet to formmail.php on the named website.
If that URL starts with "/" (such as "/formmail.php"), then it probably won't work because it won't find "/formmail.php" on the user's computer.
If that URL is just "formmail.php", then it will probably submit to formmail.php on the disk you've sent out. But, it probably won't work because the user's computer doesn't have a PHP interpreter.
So, the short answer is that it will work fine provided:
This means you can send the HTML form(s) without sending FormMail on the disk.
- You use a URL to FormMail on your website.
- The user is connected to the internet.