Chair of solid state physics . ... Defects in crystals . ... Lectures program for the undergraduate students of the Faculty of general and applied physics of Moscow Institute of Physics and Technology (State University) . The defect-free and unlimited solid is though a useful ideal construction, but it is quite far from reality. ... At the beginning, the 0-dimensional defects like vacancies, interstitials, dislocation kinks and kinks of surface steps are discussed. ... Grain boundary dislocations. ...