To get technical -- US homes get two phases of 120v that are 180 degrees out of phase with the neutral. Using either phase and the neutral gives you 120v. Using the two out of phase 120v phases together gives you a difference of 240v.

https://appliantology.org/uploads/monthly_2016_06/large.5758...

▲

ender341341 4 days ago | parent [-]

Even more technical, we don't have two phases, we have 1-phase that's split in half. I hate it cause it makes it confusing.

Two phase power is not the same as split phase (There's basically only weird older installations of 2 phase in use anymore).

	▲	kube-system 4 days ago \| parent [-]
		Yeah that's right. The grid is three phases (as it is basically everywhere in the world), and the transformer at the pole splits one of those in half. Although, what are technically half-phases are usually just called "phases" when they're inside of a home.