Nonequilibrium thermodynamics(NET)concerns with transport processes.On a mesoscopic level and in terms of statistical descriptions of dynamics,various transport phenomena can all be quantitatively described in terms of a single entity: the flux that transports probabilities following Chapman-Kolmogorov equation.This explains why mesoscopic stochastic NET attains a universal formulation and appears as a branch of applied prob ability in its abstract form.We introduce this new theory through simple example from biochemistry.