Classical physics typically included all of
physics before the theory of
relativity and the
quantum theory came into existence. Nowadays, it includes relativistic theories as well, and something non-classical would involve some quantum phenomenon. Classical physics is characterized by the philosophy of strict
determinism unlike the quantum laws (
wavefunction collapse, in particular).
Thus, it includes all of classical mechanics (the Newton's laws of motion, Lagrangian and Hamiltonian formalisms, Maxwell's Equations of electrodynamics, the laws of thermodynamics, etc...) and also the special and general theories of relativity.