It’s one of the (many) Italian words understood around the world, but it doesn’t just mean “hello” and “goodbye.” It comes from the Venetian dialect, where a phrase that sounded very much like today’s “ciao” literally meant, “I am your slave.” The gist is more like, “I’m at your service,” but the fact is that many Italians – especially older generations – think of “ciao” as far too casual for everyday use. Younger Italians use it among friends, but those same kids would probably not say, “ciao” to a grandmother. Using a more formal greeting will mean you’re less likely to get a sideways glare from the old lady at the market. Try “salve” for a greeting and either “buongiorno” if it’s morning or “buona sera” if it’s evening for goodbye.