In Korea, most lottery is called "lotto". Isn't there any difference between "lotto" and "lottery"?
I used to hear "lottery" in Korean a lot, but ever since early 1990s or something, it has changed to "lotto".
A lottery is any game of chance run for a charity or public purpose, technically. In normal use in the US, lottery games are run by the various states to raise funds for various public services. They can range from scratch-off tickets where you might win a few dollars or a few thousand; to daiily 3 and 4 digit numbers paying $500 or $5000 to one; to the big prize lottos.
Lotto is used more to describe a game or games with astronomical odds and large prizes.