How to prevent numbers in the input box and just display text?
<p>I found a script that works but I have no idea how it is working. </p>

<p>The <code>split()</code> method this example uses is giving me painful headache. Does anyone have an idea of how that <code>split()</code> method is working in this example? Can we pass numbers as first argument to <code>split()</code> method? Is that a separator, if it is why is it not enclosed within quotes?</p>

<p><strong>Script</strong></p>

<pre><code>function noNumbers(field) {
   for ( var i = 0; i &lt; 10; i++ ) {
      field.value = field.value.split(i).join("");
    }
}
</code></pre>

<p><strong>HTML</strong>    </p>

<pre><code>   &lt;form&gt;
   Type some text (numbers not allowed):
    &lt;input type="text" onkeyup="noNumbers(this);" /&gt;
   &lt;/form&gt;
</code></pre>
