title: UnityException: Tag: is not defined
body: <p>I'm following the <a href="https://unity3d.com/learn/tutorials/projects/roll-ball-tutorial" rel="nofollow">Unity Roll A Ball Tutorial</a> but I'm having an issue picking up the spinning objects. Whenever I roll over them I get this error: </p>
  
  <blockquote>
    <p>UnityException: Tag: PickUp is not defined.
    PlayerController.OnTriggerEnter (UnityEngine.Collider other) (at Assets/Scripts/PlayerController.cs:30)</p>
  </blockquote>
  
  <p>I've made sure my tag <code>PickUp</code> is exactly the same as in the code, and still it doesn't work. I've been trying to fix this for a long some so any help is appreciated.</p>