A very short pulse of energy on a power line. Power spikes can contain very high voltages – up to and beyond 6000 volts – but usually last only a few milliseconds, as opposed to longer, but lower voltage power surge. Since they occur for such a short duration of time they don’t always cause equipment failure, but the potential is there for great damage to sensitive equipment and in many instances they can be catastrophic. Worse, while equipment may not fail right away when exposed to spikes, semiconductor devices can be “weakened” and may fail later. Modern power supply technology does a remarkably good job of filtering out moderate instances of these high frequency, high voltage components on the power line. Nevertheless they do almost always cause noticeable clicks and pops in audio and frequently will corrupt data in digital equipment. For very sensitive equipment and/or critical applications, additional power line filtering and voltage clamping can be deployed to further reduce the consequences of spikes.