How to send information hidden through a form?

In input, set the hidden attribute and place the value within value , like this:

<input type="hidden" name="input1" value="valor que você quer passar">

Maybe it's not your case, but if you're doing this to implement the honeypot , where you put a hidden field to identify that your user is actually a bot spammer, input type="hidden" would not be the best form, since it is trivial for a bot to identify that field should not be filled in.

Other ways to do this are:

• in JavaScript:

  document.querySelector('input[name="NAME"]')[0].style.visibility = 'hidden';
  

  or

  document.querySelector('input[name="NAME"]')[0].style.display = 'none';
  

• in jQuery:

  $('input[name="NAME"]').hide();
  

• in CSS:

  input[name="NAME"] {
      display: none;
  }
  

Yes, a bot that has a JavaScript and CSS parser will also be able to identify that the input should not be filled in, but the above method already prevents simple bots from spamming your site.