  At thermal equilibrium, different chemical freezeout conditions have been
proposed so far. They have an ultimate aim of proposing a universal description
for the chemical freezeout parameters ($T_{ch}$ and $\mu_b$), which are to be
extracted from the statistical fitting of different particle ratios measured at
various collision energies with calculations from thermal models. A systematic
comparison between these conditions is presented. The physical meaning of each
of them and their sensitivity to the hadron mass cuts are discussed. Based on
availability, some of them are compared with recent lattice calculations. We
found that most of these conditions are thermodynamically equivalent,
especially at small baryon chemical potential. We propose that further crucial
consistency tests should be performed at low energies. The fireball
thermodynamics is another way of guessing conditions describing the chemical
freezeout parameters extracted from high-energy experiments. We endorse the
possibility that the various chemical freezeout conditions should be
interpreted as different aspects of one universal condition.
