Learn Italian: È notte. Buonanotte! - It is night. Good night!

The accent mark distinguishes È (is) from e (and). Leaving it out completely changes the meaning of the word, so it is a very important spelling rule to remember!

Why is it buonanotte instead of buonnotte?

The word notte (night) is a feminine noun. Therefore, it uses the feminine adjective buona (good) rather than the masculine buon. Over time, the two words combined into the single greeting buonanotte.

When do Italians actually say buonanotte?

You only say buonanotte when someone is literally going to bed to sleep. If it is late but you are just saying goodbye at the end of an evening out, you would usually use buonasera (good evening) instead.