Chapter 10 Gun.processHit() question

[sergeydi]

private void processHit(GameObject hitObject) 
{
  if (hitObject.GetComponent<Player>() != null) 
  {
    hitObject.GetComponent<Player>().TakeDamage(damage);
  }

  if (hitObject.GetComponent<Robot>() != null) 
  {
    hitObject.GetComponent<Robot>().TakeDamage(damage);
  }
}

I don’t understand what this code using for:

if (hitObject.GetComponent<Player>() != null) 
{
    hitObject.GetComponent<Player>().TakeDamage(damage);
}

In what case (hitObject.GetComponent<Player>() != null) can happens and why we hit self?

[ghostwolf]

It so you take damage from the robot’s rockets. And it only damage the object the player.