Fadaar
That guy
OK but it's geeky. In the US, houses/apartments are 120/240V/60hz and some apartments are 120/208V/60hz. What that means is your house panel has 2 hot legs. The voltage between one of those legs is 120V and the voltage between them both is 240 or 208.
The tanning bed I mentioned uses 230V only with a big warning that anything under 219V and anything over 231 volts will void the warranty (and the fucking thing won't even come on). That's out of our US voltage ranges so we have to add equipment (called a buck/boost xfmr) to even get it running. Thankfully it will at least work with the 60hz because that's a whole other headache. Lots of Europe and I believe parts of Canada use 50hz. If this didn't put you fast asleep I hope it helped.
I didn't even know 50 hz was a thing until I got a job in civilian aviation. It is easy everything being 115 VAC/400 hz and 28 VDC though, that's universal for planes.