Contents: Liouville Equation in Classical Mechanics; Liouville Equation in Quantum Mechanics; Canonical Distributions and Thermodynamic Functions; Two-Time correlational Functions and Green's Functions in the Theory of Thermal Equilibrium; Matrix Representation of Symmetrical Dynamical Operators; Translation from Continuous to Discrete Representations; Second Quantized Representation for Wavefunctions in Bose and Fermi Statistics; Second Quantized Representation for Dynamical Operators; General Remarks on the Second Quantization Method; Analogues of the Second Quantization Method in Classical Mechanics