Tongue bifurcation, or Tongue Splitting is a type of body modification in which the tongue is cut centrally from its tip, part of the way towards its base, forking at the end. Most who have had the procedure report that it enhances the pleasure of kissing. With a bit of practice, one learns to move the forks of the tongue independently.
Tongue bifurcation is, however, not necessarily a surgical procedure. Self modifiers often choose to achieve a split by gradually tightening nylon bindings inserted through an existing tongue piercing over a long period of time.