IS Array validation in javascript

var playerKills = 5;

if( Object.prototype.toString.call( playerKills ) === '[object Array]' ) {
    alert( 'Array!' );
}else{ alert('No');}

Cookies set up using Javascript

<script>     
var cname = 'Afro';
        var cvalue = 'No';
        var exdays = 14; // No.of days
        var d = new Date();
        d.setTime(d.getTime() + (exdays*24*60*60*1000));
        var expires = "expires="+d.toUTCString();
        document.cookie = cname+"="+cvalue+"; "+expires;
</script>