This two forms in this example are identical, except the first is a member of the visibleIf-submitInvisibleData class, and the second isn't. Try submitting both forms without filling out any of the fields. You will notice the first one submits all the field values, even the hidden ones, while the second doesn't submit the hidden fields. Back to User Agent Man visibleIf article
Personal Information

Please enter in the following information about your phone

Name :
Age Verification : I am over the age of 18
Address :
City :
Province/State :
Postal/Zip Code :
Personal Information

Please enter in the following information about your phone

Name :
Age Verification : I am over the age of 18
Address :
City :
Province/State :
Postal/Zip Code :