Exponential family

A class of probability distributions whose density or mass function can be written as f(x|θ) = h(x)·exp[η(θ)·T(x) − A(θ)]. Includes the Normal, Binomial, Poisson, Gamma, and Bernoulli distributions. The family admits sufficient statistics, conjugate priors, and a unified information-geometric structure, making it central to statistical theory.