 The collection of procedures that may be grouped under classical statistics is vast and multi-faceted. By and large, classical statistical procedures share the feature that they only rely on probability assignments over sample spaces. As indicated, an important motivation for this is that those probabilities can be interpreted as frequencies, from which the term of frequentist statistics originates.  Classical statistical procedures are typically defined by some function over sample space, where this function depends, often exclusively, on the distributions that the hypotheses under consideration assign to the sample space. For the range of samples that may be obtained, the function then points to one of the hypotheses, or perhaps to a set of them, as being in some sense the best fit with that sample. Or, conversely, it discards candidate hypotheses that render the sample too improbable. 