Entropy is the fundamental notion in statistical physics and it is understood to be the measure of disorder. Probability and statistics are for the rule of uncertainty in measure on the terms of calculus. Combinatorics is for rule of uncertainty in order, what precedes the other, on binary terms. For deterministic situation in physics we consider the Cartesian coordinate system for analysis. But in statistical physics we model situations according to the criterion of the phase space with six coordinates, 3 space and 3 momentum components. Both probability and combinatorics considerations are distributional.