180 switch is a phase reversal option that fully corrects a 180° phase inversion, keeping in mind some pedals are odd amount shifting.
Phase is indeed an electronic phenomenon. If I understood it properly I might have become an electrical engineer.
If you throw a tennis ball against the ground so it bounces against a wall and loops back to drop into your hand and threw another as it was hitting the wall then the two balls are out of phase with respect to their altitude 'signals' by crudely 180°. Ignoring the crudeness we could look at ideally thrown and bouncing balls...
Now if your mate stands further back and throws his ball harder so it bounces higher but comes back to his hand at the same time as yours you are in phase and the sound of your ball has a higher pitch added on top of the original. But if instead your mate throws his up against the wall and it bounces back to him off the ground you get a cacophony of bounces.
Importantly, unlike tennis balls bouncing the brain does not notice small discrepancies of phase when summing audio. Nor does it notice differences in phase reproduction across the spectrum.