Noise Gates are a very simple but useful piece of kit if you like a guitar with single coil pick ups like a Strat or Tele.
As we know, lights and other stage equipment can leave you with an embarrassing hum or feedback between songs, especially from a high gain guitar amplifier. Put your noise gate in the effect loop, or after that noisy pedal and turn down the noise without it altering the tone. If you like High Gain, then you will have heard that hiss.. A noise gate will sort it.
A noise gate guitar pedal will cut that noise dead, literaly close a gate on it. Prevent trailing high gain feedback when pushed to the limits, small adjustments make a big difference