Two phase power is very, very rare. You are probably thinking of split phase power which is a form of single phase power. It is ubiquitous in American residenti

Two phase power is very, very rare. You are probably thinking of split phase power which is a form of single phase power. It is ubiquitous in American residential power. It takes the form of two hots at 240VAC with a neutral between them, allowing you to get 120VAC from the neutral and either hot.