An electromagnetic pulse (EMP) is a brief burst of electromagnetic energy that can occur naturally or artificially. EMPs can be caused by lightning strikes, electrostatic discharge, power line surges, nuclear explosions, and non-nuclear directed energy devices. EMPs can disrupt communications and damage electronic equipment, and can physically damage objects such as buildings and aircraft.

A nuclear electromagnetic pulse (NEMP) is a burst of electromagnetic radiation created by a nuclear explosion. The resulting rapidly varying electric and magnetic fields may couple with electrical and electronic systems to produce damaging current and voltage surges. The specific characteristics of a particular NEMP event vary according to a number of factors, the most important of which is the altitude of the detonation.

The impact of an EMP attack in the US would be catastrophic, as it can shut down vast areas of electric grids, systems, and devices while drastically overheating, degrading, or destroying their components. Essentially, any electronics system that is not protected against extreme EMP events may be subject to either the direct "shock" of the blast itself or to the damage that is inflicted on the systems and controls upon which they are dependent. Experts argue that the US is incredibly ill-prepared for such an event, with former CIA director James Woolsey calling it “one of the greatest national vulnerabilities” .

To protect electronics from EMP, one can use the RF Shielding technique (electromagnetic radiation or electromagnetic shielding) where electromagnetic risks are mitigated and the electromagnetic field is effectively blocked with barriers of magnetic materials. There are many ways to create EMP protection, which include using Faraday cages, surge protectors, and grounding.