An Electronic Countermeasure (ECM) refers to techniques used to prevent or reduce the effectiveness of enemy electronic systems. This can include jamming radar signals, disrupting communication systems, or deceiving sensors. ECM is crucial in military operations to protect assets and maintain operational security. ECM can be employed in various forms, such as jamming devices that emit signals to interfere with enemy communications or decoys that mislead radar systems. These measures help ensure that military forces can operate effectively while minimizing the risk of detection or targeting by adversaries.