This lecture covers axisymmetric models for disk galaxies, including potential of infinite thin disks, Lagrangian and Hamiltonian mechanics, orbits in spherical potentials, radial and non-radial orbits, examples like Keplerian orbits, and orbits in isochrone potentials. It also discusses the potential theory of infinite thin disks, Mestel disk, exponential disk, circular velocity, and potential of infinite wires and slabs with oscillatory surface density.