title: gameObject.GetComponent<RigidBody>() vs. gameObject.rigidbody
body: <p>There are two ways to access RigidBody Component in gameObject:</p>
  <ul>
  <li><code>gameObject.GetComponent&lt;RigidBody&gt;()</code></li>
  <li><code>gameObject.rigidbody</code> (read only)</li>
  </ul>
  <p>I would like to understand the reason for the (a bit redundant) read-only one in the light of the fact that there are no read-only properties for other Components like BoxCollider.</p>