This is a demonstration of layers. When the green flag is clicked, the helicopter goes "back" 1 layer and the cloud on the right goes "back" 2 layers. That means that the helicopter is behind the cloud on the left, but the cloud on the right is behind the helicopter. Then the helicopter glides back and forth. In order to keep the helicopter looking forward, there is code in the helicopter loop to make it turn in the correct direction after each glide. Also the helicopter's rotation style is set to left and right (using the "i" button on the sprite).
