The book contains an up-to-date overview of the physics and technology of the man-made artificial atoms, i.e. the quantum dots. Different methods of creation of quantum dots, and the mechanism of carrier confinement in these structures are described. Discussed are the fundamental properties of these quasi-zero-dimensional many-electron systems, such as the single-particle energy quantization, generalized Kohn theorem, the effects due to electron-electron and spin-orbit interactions, magic states and the composite fermion formation in high magnetic fields, and the interaction of a dot with the visible and far-infrared light. The review of experiments carried out on quantum dots includes the capacitance, photoluminescence, and far-infrared spectroscopies. The original part contains the detailed analysis of the atomic-like properties of self-assembled quantum dots (shell structure, Hund rules, exciton condensation), the discussion of the effects due to the spin-orbit interaction (revealed in capacitance and far-infrared spectroscopies), and the description of the structure of luminescence spectrum of a quantum dot in terms of metastable excitonic states (also in a magnetic field).