Countermeasure


A countermeasure is a measure or action taken to counter or offset another one. As a general concept it implies precision, and is any technological or tactical solution or system designed to prevent an undesirable outcome in the process. The first known use of the term is in 1923.
Countermeasures can refer to the following disciplinary spectrum:
Defense countermeasures are often subdivided into "active" and "passive" countermeasures.

Active

In military applications, "active" countermeasures which alter the electromagnetic, acoustic or other signature of a target thereby altering the tracking and sensing behavior of an incoming threat are designated soft-kill measures. Measures that physically counterattack an incoming threat thereby destroying/altering its payload/warhead in such a way that the intended effect on the target is majorly impeded, such as close-in weapon systems, are designated hard-kill measures. Both types are further described in active protection systems.

Passive

"Passive" countermeasures include: