Object and Animation Basics - Blender Foundations: The Essential Guide to Learning Blender 2.6 - page 53

Finally, Cornelius has been set as Beatrice's child in the same way.
What you end up with is a chain of parent-child objects. Transforming Suzanne moves the rest of
her brood. Moving Alexander transforms all of his siblings, but does not affect Suzanne. Transforming
Beatrice moves only herself and Cornelius. Directly moving Cornelius does not affect anything else.
Rotating Suzanne rotates the whole chain of child objects around her, as though they were attached to a
string.
A parent-child relationship can be broken by selecting the child and pressing Alt-P .
You can check the Web Bucket for a video of these monkeys, animated ( suzanne_and_kids.mpeg ) .
One last note on parents and children. Often in tutorials and other topics you will see the creation of
parent-child structures simply referred to as “parenting.” The way it is said is usually “Parent Cornelius to
Suzanne.” Although it's not actually accurate, this means that the tutorial wants you to make Cornelius
the child of Suzanne.
Empties
While you're working in 3D, organizing your scenes and animating, you might find that you need an
object for purposes of parenting, marking a location or something else, but you don't need it to actually
render. For example, you might have a car that drives around and around in a circle. You could keyframe
the car around a circular path, but much easier is to make it the child of a central object and animate
that object's rotation. The car will move in a perfect circle. Blender provides a kind of dummy object for
these constructive purposes that never renders and takes up almost no processing time or memory: the
Empty .
Empties are added through the Shift-A menu, at the top level. By default, Empties look like a three-arrowed
axis, which lets you determine their orientation at a glance. On the Object Data context of the Properties
window though, you can change the visualization depending on your needs. Figure 3.27 shows several
Empties, with different visualizations.
Instancing and Duplicating
The last general object task we
need to cover is duplication. The
trees back in Figure 3.24 were not
each created individually. I made
one, then duplicated it to make
the rest.
Selected objects are duplicated
with Shift-D . Newly duplicated
objects are born in Grab trans-
formation mode, allowing you to Figure 3.27 A cavalcade of Empties.