return 'Balance' . $this->balance; // same result when return 'balance'.$this->balance; } public function withdrawn($amount) { // displaybalance is method if ($this->balance < $amount) { echo 'not enough money'; // HERE U CAN ALSO USE THROWING EXCEPTIONS } else { $this->balance = $this->balance - $amount; // same result when return 'balance'.$this->balance; } } public function Deposit($amount) { $this->balance = $this->balance + $amount; } } class SavingAccount extends BankAccount { } $piyush = new BankAccount(); $piyush->Deposit(100); $piyush->Withdrawn(20); $piyush_saving = new SavingAccount(); $piyush_saving->Deposit(300); echo $piyush->DisplayBalance() . '<br>'; echo $piyush_saving->DisplayBalance(); ?>