Unity, what are the GameObject and how manipulate them

GameObjects are the objects in the scene, so the camera is a gameObject, the light is a gameObject and so on.

To manipulate gameObject, we need pay attention at this panel above the hierarchy.

Every time you highlight an object, normally first tool selected is the move tool (the directional cross)
With that you can move the gameObject in the scene.

The next tool is the Rotate tool, and you can rotate the object in every axes you want.

If you notice something strange is because every time I rotate the light the lighting in the scene change, and becoming brighter or darker, depending on inclination.

The next tool is Scale tool.
With that you can change the dimension of gameObject in the scene.
You can take only one axes

or every axes if you click here

In this example you see the stretch, and if you look in the inspector under scale, we see something happen, but nothing for real.
In the next articles, when we create a game and use many gameObject, you see this funcionality at work.

The next tool is Rect tool, and you need for scaling the UI object, but this a little bit advance topic and we talk about later.

At the moment the real useful tool are Move, Rotate and Scale, the other are for next lecture.

LITTLE SHORTCUT : when we highlight a gameObject, if you press Q, W, E, R, T, Y, we can select the tool we need without move the mouse every time.

As you can see, I can select the tools without move my mouse.

The Hand tool, the first one, is for the overview.
Hold on the left click and move around.

This is how we manipulate the gameObject in Unity.