WorldInfo { }
  PROTO Humanoid [ ... ]{ ... }
  PROTO Joint    [ ... ]{ ... }
  PROTO Segment  [ ... ]{ ... }
  PROTO Site     [ ... ]{ ... }
  
  PROTO Humanoid-raven [
   (a)interface of Humanoid
   (b)interface for STEP
  ]{ ## body
  DEF Humanoid Humanoid {
  ...
   (c)script to export H-Anim names
  } ## end Humanoid
  } ## end PROTO