CODE EXAMPLE FOR PHP

error php

// how to display php errors on your browser : 
// first step, create an error function : 

$errors = array();

// now you have just to insert the function like this : 

if (........){
  $errors['the_name_of_the_error']='the error message';
}

// example : 
// we want to display an error when the user does not correctly fill, 
// in the 'password' box when registering on your website : 

if(empty($_POST['password']) ||
   $_POST['password'] != $_POST['password_confirm']){
	$errors['errors']= "You must enter a valid password";
}