/////////////////////////////////////////////Task 4 /////////////////////////////////////////
		//This variable is Global because it is declared outside of any functions.
		//Thus all functions can access it using the $GLOBALS array.
		$TotalSum = 0;
		
		function AddValue($value){
			//This variable even though have the same name
			//as the variable in global is still local thus any
			//changes made to it would not affect the global variable.
			//and it is also not accessable outside of this function.
			$TotalSum = 23;
			
			echo "AddValue Local variable TotalSum = $TotalSum";
			echo "<br>";
			echo 'Global TotalSum or $GLOBALS['. "'TotalSum'] = ". $GLOBALS['TotalSum'];
			echo "<br>";
			echo "Adding $value to the global TotalSum Variable.";
			echo "<br>";
			
			$GLOBALS['TotalSum'] += $value;
			
		}
		
		function say_hello($it){
			//The variable $it is received by value thus nothing that
			//happens in the function can change the original value.
			
			echo '	Hello, '. $it;
			$it = 'I am no longer '. $it;
			
		}
		
		function say_hello2(&$it){
			//The variable &$it is received by reference thus all changes made to &$it that
			//happens in the function will change the original value.
			
			echo '	Hello, '. $it;
			$it = 'I am no longer '. $it;
			
		}
/////////////////////////////////////////////Task 4 A /////////////////////////////////////////		
		Echo '<H1>Task 4: A</H1> <br><br>';
		$MyName = 'John Smith';
		Echo '$MyName = '. $MyName;
		Echo '<br>Calling SayHello using by value.<br>';
		say_hello($MyName);
		Echo '<br><br>';
		
		Echo 'Check if $MyName is still the same value:<br>';	
		Echo '$MyName = '. $MyName .'<br><br>';
		
		Echo 'Calling SayHello2 using by Reference.<br>';
		say_hello2($MyName);
		Echo '<br><br>';
		
		Echo 'Check if $MyName is still the same value:<br>';	
		Echo '$MyName = '. $MyName .'<br><br>';
		
/////////////////////////////////////////////Task 4 B /////////////////////////////////////////		
		Echo '<H1>Task 4: B</H1> <br><br>';
		Echo 'Global TotalSum or $GLOBALS['. "'TotalSum'] = ". $GLOBALS['TotalSum'];
		Echo '<br><br>';
		AddValue(5);
		Echo 'Global TotalSum or $GLOBALS['. "'TotalSum'] = ". $GLOBALS['TotalSum'];
		Echo '<br><br>';
		AddValue(10);
		Echo 'Global TotalSum or $GLOBALS['. "'TotalSum'] = ". $GLOBALS['TotalSum'];
		Echo '<br><br>';
		AddValue(5);
		Echo 'Global TotalSum or $GLOBALS['. "'TotalSum'] = ". $GLOBALS['TotalSum'];
		Echo '<br><br>';