Combinatorics is an educational program taken from TV Ontario's In-Class video collection. MIT Professor Peter Shor hosts the series and explains to interested viewers the theory behind permutation and combination. Shor uses a classroom setting to put complicated subjects into layman's terms, mixing 3D animations with his discussion. The lecture opens with "A Dicey Beginning" and introduces combinatorics by using a couple of die. Shor rolls the dice on a table to explain Pascal's theory of probability of a given outcome from game with repetitive numbers. The dice game segues into the fundamental counting principle, where the professor explains how people's choices arise from a given set of possibilities. In the permutations and combinations segment, Shor uses a 3D graph to show viewers how to determine the order of things and how this determination defines the two subjects. Expanding binomial expressions appears in the fourth installment, and Shor ends the series with a discussion on simple combinatory problem solving.