Contents: Nonlinear Problems in 1 + 1 and Their Linearization; Classical Field Theory Models; Hamiltonian Formulation, Action-Angle Variables, Solitons, Classical Lattice Models and Lattice Approximants of Classical Fields; Quantization on a Lattice: Relationship Classical-Quantum; Quantization on a Lattice: Simple Bose Models; Spin 1/2 Lattice Systems Related to Nonlinear Bose Problems: Lattice Fermions; Quantization in Continuum: Joint Bose-Fermi Spectral Problems in 1 + 1; Quantum Meaning of Classical Field Theory for Fermi Systems; On Infinite Constituent "Elementary" Systems: Canonical (Constituent) Quantization of Soliton Fields; Towards 1 + 3: Problems and Prospects;