​x
 
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Interactive Example</title>
    <script>
        function calculateSquare(number) {
            return number * number;
        }
​
        function showSquare() {
            let number = document.getElementById("numberInput").value;
            let result = calculateSquare(number);
            document.getElementById("result").innerText = "Square: " + result;
        }
    </script>
</head>
<body>
    <input type="number" id="numberInput" placeholder="Enter a number">
    <button onclick="showSquare()">Calculate Square</button>
    <p id="result"></p>
</body>
</html>