This chapter begins with a review of the basic principles and equations of classical mechanics. These lead naturally to the Liouville theorem, which together with the notions of ensemble and phase space, give rise to the Liouville equation. This equation is perhaps the most significant relation in all of classical kinetic theory, and in the remainder of the chapter various techniques of solution to this equation, as well as various interpretations of its solution, are presented. Thus, for example, it is found that the Liouville equation is an equation of motion for the TV -particle joint-probability distribution, where TV denotes the number of particles in the system. Integration of this distribution over subdomains in phase space gives reduced distributions whose equations of motion (BBKGY Eqs.) are developed in Chapter 2.