Armature Symmetry is used to create and maintain perfectly symmetrical skeletons. It distinguishes between 3 types of bones:

1. Left/right side bones. They have a suffix determining the side they belong to. By default Armature Symmetry expect the suffixes ".L" and ".R".
2. Centered bones. The bones that are not explicitely excluded (see 3.).
3. Excluded bones. By default all bones with the suffix ".X" are excluded and will not get modified by Armature Symmetry.

Armature Symmetry handles one side of the armature as reference and will automatically create or adjust the bones on the other side. By default the right side (".R") is the reference side.

 

To be continued...