The textbook presents in a systematic manner a set of issues related to the damaging effects of weapons and ammunition. The basic concepts of the theory of effectiveness, the physical basis of the functioning and damaging effects of fragmentation, cumulative, high-explosive and penetrating weapons are considered. Calculation formulas are given that allow one to estimate the parameters of the affected fields and their interaction with various objects. Damage criteria are given, characteristics of the vulnerability of objects in relation to various damaging factors are given, dependencies are presented for assessing safe distances and the resistance of various structures in relation to the effects of explosion and impact. Issues related to the use of numerical modeling of explosion and impact processes are considered.