Use the Manipulators to quickly change your object's:
These are known as transformations. You can also edit these properties in the Inspector.
The Manipulators are at the 3 icons at the top of the Viewport:
Select the first icon to change an object's position, the second to rotate the object and the third to change the scale.
When you've selected an object and a Manipulator, you'll see axis or arrows appear on that object in the Viewport:
Click and drag these axes, or the object itself, to transform the object.
In the example below, we selected a 3D object that looks like a diamond and clicked the first Manipulator icon - for position.
We then dragged the green axis to change the position of the object, moving it along the Y axis so it's no longer in the box:
You can also change the position or size of an object across all axes by clicking and dragging the yellow cube in the center of the object:
Or, click and drag the red, blue or green square to scale the object on 2 axes only.
If part of the manipulator is greyed out, it means you can't change that transformation for the object you've selected.
When an object is a child of another object, it can either be transformed:
In the the image on the left we've selected Global co-ordinates. On the right we've selected Local. The axis has changed, because the position is set based on where the object is positioned within its parent:
Choose Pivot or Center to switch between manipulating an object around its own pivot point, or a central pivot point.
You'd usually use this feature to transform multiple objects, either around their individual pivot points or a central point.