We describe the basic principles of nanoparticle synthesis by conventional pulsed laser ablation. The generalization of the Zeldovich and Raizer theory of condensation has been performed for inhomogeneous laser-induced plume where the rates of nucleation as well as the condensation times are different for different parts of the plume. The theoretical development and analysis of the experimental results are given for condensation, expansion and properties of silicon nanoclusters.