In this work understanding of black holes in the context of chemistry will be presented which includes the concepts of Van der Waals fluids, reentrant phase transition and triple point etc. This is done by giving the comparison of thermodynamic laws of ordinary thermodynamic system to the corresponding thermodynamic laws of black holes. In this framework the cosmological constant is considered as thermodynamic pressure, mass is considered as chemical enthalpy. This comparison will lead us to understand the black holes in a new perspective, called the black hole chemistry. In this framework both charged and rotating black holes will be discussed. Due to this change in perspective on the role of black hole mass and the inclusion of the cosmological constant as a pressure term has recently been shown to have a number of remarkable consequences for black
hole thermodynamics, making their behavior analogous to a variety of “everyday” chemical phenomena. One such indicator was the realization that charged black holes behave as Van der Waals fluids. Van der Waals equation modifies the equation of state for an ideal gas to the one that approximates the behavior of real fluids. In this framework thermodynamic of black holes is presented in extended phase space.