Here’s what they taught us in elementary school (Northern Virginia, early 1960s):
Rain: water coming out of the sky
Snow: fluffy white stuff coming out of the sky
Sleet: tiny ice pebbles coming out of the sky
Hail: bigger ice bits coming out of the sky
Not from elementary school, but more or less contemporaneous:
Slush: a mixture of snow and water on the ground
Freezing rain: really cold water coming out of the sky that freezes when it hits the ground
Wintry mix: a mixture of two or more of snow, sleet, and at least one kind of rain as defined above
When my wife and I lived in Bristol VA/TN which is at about 1700 feet above sea level, we saw hail a few times a year, I’d guess. It would generally be pretty spherical up to about penny- or nickel-sized, but if it got any bigger than that, the shapes would get more irregular. And it wasn’t just a winter thing; some of the bigger hailstorms we had were well into spring.
But everywhere else we’ve been, hail has been a rarity. Not quite mythical, but more like a once-a-decade event.