One of the directions of nanotechnology is the production of nanopowders (NPs). Nanopowders, according to the currently widely used classification of nanomaterials, belong to zero-dimensional systems in which the limitation of wave functions occurs in all three directions. This book presents a new method for producing simple and complex metal oxide and fluoride nanopowders, based on the “evaporation-condensation” process using pulsed electron beam evaporation (PEBE). It presents the results of more than 10 years of study of the characteristics of nanopowders produced using the aforementioned method. The produced NPs are mesoporous and suitable for use in various applications such as medical diagnostics, nanoelectronics, optics, spintronics, dosimeters, and photocatalysis. The book will be useful for the researchers in nanotechnology, physical chemistry, biomedicine, and pharmaceuticals, especially those with an interest in drug delivery or cancer therapy.