Next, we need to create some objects in our scene or we will have a very boring game. The first object we need to create is something to represent the ground. Yes I know there is no ground in space, but to illustrate some of the available features we need the ground.
In the Main Menu, create a new plane by selecting GameObject | Create Other | Plane.
We also want to give this Plane a unique name, so in the Inspector view change the name of the object from Plane to Ground by selecting the Plane text in the Inspector by simply replacing it with Ground. Unity will now refer to this object as Ground as well. This will come in useful later when we're trying to do things with the ground plane:
In the Inspector, increase the size of our ground plane by changing the Scale to (100, 1, 100). This should give us plenty of room to move around:
One new feature of Unity 3 is the ability to get a quick render of what the world looks like from the camera's perspective without having to play the game. In the Hierarchy view select the Main Camera object and you will see in the Scene view that there is a Camera Preview window that is showing you what the camera sees. This window is a real-time preview as well, so as objects change in the scene, the Camera Preview will update to reflect those changes:
What just happened?
We have just created a simple ground object for our Hello World scene and explored how we can preview the world with the Camera Preview.