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<html><body><h1>JavaScript Global Properties</h1><h2>The undefined Property</h2><p id="demo"></p><script> if (typeof y === "undefined") { text = "y is undefined"; } else { text = "y is defined"; } document.getElementById("demo").innerHTML = text;</script></body><!-- /jsref/tryit.asp?filename=tryjsref_undefined2 Thu, 06 Feb 2025 18:35:42 GMT --></html>