A pulse of intense electromagnetic radiation generated by certain physical events, especially by a nuclear explosion. The pulse includes a continuous spectrum of low frequencies and can interfere with the operation of electrical equipment. - The American Heritage Science Dictionary
An electromagnetic bomb or E-bomb is a weapon designed to disable electronics with an electromagnetic pulse (EMP) that can couple with electrical/electronic systems to produce damaging current and voltage surges by electromagnetic induction. - Wikipedia
Important things that won't work after an attack:
Note that these are all critical communications medium.
I guess my statement here is: I'm glad my guns will still work after an EMP attack by the enemy.
Self Defense and Self Preservation folks. Think about it.
I ask, sir, what is the militia? It is the whole people, except for a few public officials. To disarm the people is the best and most effectual way to enslave them.
- George Mason