I copied a php mailForm from somewhere and incorporated it into my contact form. I expected the form data to be mailed to my email address but it was not, despite the fact that upon submission of the contact form on the website, it displayed a success message[color=#000099][/color]

Set the php debug flag on so u will see the error

$mail->SMTPDebug = 1;
Will do the trick

Thanks, please kindly give me a detailed guidance on what to do(or how to do it), I'm a front-end dev with no php or back-end experience

Thanks, I've done what you suggested that I should do, the error message I got (displayed on the webpage) is something like;
'Creating default object from empty value in /home/myFolderName/public_html/contact.php on line 15'
I insert - $mail->SMTPDebug = 1; - into line 15, just the closing ?> php tag. Please, what should I do next