Nanoclusters, in their structure and properties, are in an intermediate state between small molecules and a massive material. This article is about , How to get nanoclusters , described their main physical and chemical properties and the ability to control them from a theoretical point of view and also considered the features of the application of the X-ray absorption spectroscopy method for the study of certain types of nanoclusters. The monograph is provided with specific examples of studies of the geometric and electronic structure of nanoclusters, which were conducted at the Scientific and Educational Center "Nanoscale Structure of Matter" of the Southern Federal University .. The book can be useful for both undergraduate and graduate students, as well as researchers leading research in the field of nanotechnology ..