To move GameObjects (or alter their Transform component), manipulate the Gizmo handles or type values directly (in numbers) in the Transform component fields in the Inspector.
Alternatively, you can select each of the four Transform modes with a hotkey: W for Move, E for Rotate, R for Scale, T for RectTransform and Y for Transform.
The Gizmo handle position toggles are used to define the location of any Transform tool Gizmo, the handles are used to manipulate the Gizmo itself.
Pivot positions the Gizmo at the actual pivot point of the GameObject, defined by the Transform component.
Center positions the Gizmo at a center position based on the selected GameObjects.
Local keeps the Gizmo’s rotation relative to the GameObject’s.
Global clamps the Gizmo to world space orientation.
You can move two axis at once while a third axes keeps still by dragging around one of the three small squares at the center of the Move Gizmo. The last axes you changed will be colored yellow.
While holding down Shift while clicking and dragging the center of the Move Gizmo, the center will change to a flat square indicating that you can move the GameObjects around relative to the direction the Scene View Camera is facing.
Scale individual or multiple GameObjects evenly on all axes at once.
Change the GameObject’s rotation by click dragging any of the axes that appears around the selection wire.
Alternatively click drag the outermost circle to rotate the GameObject around the Scene view z-axis.
Commonly used for positioning 2D elements, but can be useful for manipulating 3D GameObjects.
Combines the Move, Rotate and Scale tools providing handles for both movement and rotation. When the Tool Handle Rotation pivot is set to Local, the Transform tool also lets you scale the GameObject(s). Hold down the Shift key to enable Screen Space mode which will manipulate the position, rotation and scale of GameObjects as they appear on the screen, rather than in the Scene.
Unity also provides three types of snapping GameObjects. World grid snapping, Surface snapping and Vertex snapping, here you can find more information about it.
While using the Rotate tool, hold Shift and Control (Cmd on Mac) to rotate the GameObject towards a point on the surface of any Collider.