function userAccess() {
           
            var javascriptMessage;
            javascriptMessage = document.retrieveMessage.value;
            return javascriptMessage;
        }
 
       onclick="alert( 'JavaScript is a very important programmming language.  
       
       It brings faster user experiences, user interface interactivity and 
       
       plays a big role in making websites responsive.', userAccess() );" />

      

The output of this program is ->