  The area law of Bekenstein-Hawking entropy of the black hole suggests that
the black hole should have a lower-dimensional holographic description. It has
been found recently that a large class of rotating and charged black holes
could be holographically described a two-dimensional (2D) conformal field
theory (CFT). We show that the universal information of the dual CFT, including
the central charges and the temperatures, is fully encoded in the
thermodynamics laws of both outer and inner horizons. These laws,
characterizing how the black hole responds under the perturbation, allows us to
read different dual pictures with respect to different kinds of perturbations.
The remarkable effectiveness of this thermodynamics method suggest that the
inner horizon could play a key role in the study of holographic description of
the black hole.
