When you meet someone for the first time, the first word you'll use to greet them is Hajimemashite which means "nice to meet you", Ohayou (おはよう) means "good morning" in Japanese. You can use this greeting when addressing someone close to you, such as family, friends. It's a casual and friendly way of saying "hi" as well.

In contrast, Ohayou gozaimasu (おはようございます) is the most commonly used formal expression in Japan to say "good morning". This more formal greeting is appropriate for professional contexts, when addressing superiors, clients.

Konnichiwa (こんにちは) is used to say "good afternoon".

Oyasuminasai (おやすみなさい) means "good night".

Sayonara (さよなら) means "good bye".