Call different function for each button in Javascript

<button onclick="function1()">button 1</button> <button onclick="function2()">button 2</button> <button onclick="function3()">button 3</button> <button onclick="function4()">button 4</button> <script> function function1(){ alert("You have clicked the button 1") ; } function function2(){ alert("You have clicked the button 2") ; } function function3(){ alert("You have clicked the button 3") ; } function function4(){ alert("You have clicked the button 4") ; } </script>