So I know very little javaScript and am watching a tutorial and I'm trying to update the title field with whatever goes in a textbox. Yet, although I see no difference in my code and that of the tutorial, my function fails to substitute the text box entry if the length of the entry is greater than 0 unlike the guy in the tutorial. I have relentlessly searched the code for errors and cannot find it.

```
<!DOCTYPE html>
<html>
<head>
    <title>JavaScript Example</title>
    <script type="text/javascript">
        function substitute()
        {
            var myValue = document.getElementById('myTextBox').value;
            if (myValue.length == 0)
            {
                alert('Please enter a real value in the text box!');
                return;
            }
            var myTitle = document.getElementbyId('title');
            myTitle.innerHTML = myValue;
            return;
        }
    </script>
</head>
<body>
    <h1 id="title">JavaScript Example</h1>
    <input type="text" id="myTextBox" />
    <input type="submit" value="Click Me" onclick="substitute()" />
</body>

</html>

```