While loop in javascript.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>While Loop</title>
</head>
<body>
    <script>
        var a = 0;
        while(a<10){
            document.write(a +"<br>");
            a++;
        }
        var a = 0;
        while(true){
            if(a==5)
                break;
                document.write(a +"<br>");
                a++;
            
        }
    </script>
    
</body>
</html>