Javascript object is not function
<p>I'm new to Javascript and am confused about the error messages I get:</p>

<p>I have the JavaScript Code:</p>

<pre><code>function tile(x,y) {
return ((worldw * y) + x);
}

alert(tile(5,5));
</code></pre>

<p>But I get the error message in Chrome that "Object is not a function".</p>

<p>How can I fix this and what does the error message mean?</p>
