Variables defined with const cannot be Redeclared
Variables defined with const cannot be Reassigned
Variables defined with const have Block Scope
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<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
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<title>JavaScript</title>
<script>
let z = "Hello World";
document.write(z);
</script>
</head>
<body>
</body>
</html>