title: Real time updating of values on a form
body: <p>Slightly related to my other question (which was answered) <a href="https://stackoverflow.com/questions/6438579/html-form-not-working-properly">here</a>, I was wondering if the following was possible (it likely is and very basic but I'm a bit noobish at JavaScript)!</p>
  
  <p>So I have 2 input fields where the user types something into a form. They press "calculate" and then the function totals up what they have entered and then calculates 1,2 and 3% for each value respectively. It looks something like this:</p>
  
  <p><code>input 1%value</code><br/>
  <code>input 2%value</code><br/>
  <code>input 3%value</code><br/>
  <code>total total</code></p>
  
  <p>Is there a way for me to be able to update the form in real time? So by this I mean, as soon as the user enters a value into a field the function automatically starts updating the values such as total etc? How would I go about achieving this, can it be done purely in JavaScript?</p>
  
  <p>Thanks</p>