That’s actually a recent phenomenon. Before the age of electronics most household appliances either worked with AC or DC equally well (like incandescent bulbs) or worked well with AC only given the technology at the time (think anything with a motor, fans, HVAC compressors etc).

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analog31 6 hours ago | parent [-]

Taking it to an extreme, the house I lived in while in grad school had wall lamp fixtures that doubled as electric and gas lamps. At some point I imagine it would have been possible to choose between using electric or gas by either flipping the switch or turning a valve. They said "Edison Patent" on them. We could have lit the house on AC, DC, or gas.

Thinking about the failure modes gave me the heebie jeebies, but the gas had been disconnected ages prior.

	▲	eszed an hour ago \| parent \| next [-]
		I lived in a 19th century house in San Francisco that had gorgeous plaster work medallions on the ceilings - think cherubs and fruits - in the middle of which were the light fixtures. One day my dumb-ass flatmate made an ill-advised attempt to DIY his light fixture and cracked the still-active gas line embedded in the ceiling. Sometime in the 1920s - the date was printed on a sticker in the electrical panel - when they electrified the house, they'd wrapped the electrical wires around the gas pipes, and left them otherwise in situ. Crazy stuff.
	▲	jazzyjackson 5 hours ago \| parent \| prev [-]
		It’s kind of fun that light switches predate electricity. I think you used to turn a key, I guess you were turning a valve? Now that I think of it using a key to operate a valve makes a lot of sense but you don’t see it too often, well, I guess you want to turn things off without needing to find a key…