Changing HTML Text

<!-- Replacing selected text via html tags -->

<html>
<body>
    <!-- Button -->
    <!-- Put function name in onClick -->
    <input type="button" value="Click me!" onClick="changeText()" />

    <!-- You must use an id for the javascript to fetch, here we are using a "p" tag -->
    <!-- Put original text in here  -->
    <p id="test">This is a test.</p>

    <!-- Code -->
    <script type="text/javascript">
        function changeText(){
            document.getElementById("test").innerHTML = "This is not a test";
        }
    </script>

    <!-- Here, we have successfully changed "This is a test" into "This is not a test" -->
</body>