Comment 2 for bug 170275

Bones will work this way:
-You can attach (groups of) points to bones, so when you
rotate a bone the points are rotated.
-You can specify which bone is the son of another, so when
you rotate a parent, the sons are rotated (and the points
attached to them).
-The bones rotate around their base.(like they do in the real
world)

The bone (or skeletical) system is useful to draw elements
based on parts that follow a hierarchy. Imagine you are
drawing a character in different poses.

This system is usual in 3D programs, like Blender. Here you
can find an example:
http://download.blender.org/documentation/html228/x5638.ht
ml

But it's not only useful in 3D, a vector drawing (and
animation) tool like Moho uses it, you can see an screenshot
in their page that shows this:
http://www.lostmarble.com/moho/screens/3.jpg

If something is not clear is probably because of my english.
So ask whatever you want if you have any doubts and I'll try
to explain it better.

--Pau