Japanese has a rich set of greetings that vary by time of day, formality, and the closeness of the relationship. The most common general greeting is こんにちは (konnichiwa), meaning "Hello" or "Good afternoon," used from late morning through evening. In the morning, speakers use おはようございます (ohayou gozaimasu) in polite situations, while the casual おはよう (ohayou) is appropriate among friends and family. As evening falls, こんばんは (konbanwa) replaces こんにちは for "Good evening." When parting, さようなら (sayounara) signals a longer or more formal farewell, whereas the casual じゃあね (jaa ne) or またね (mata ne) is used among friends.
Expressions of gratitude and apology are equally important. ありがとうございます (arigatou gozaimasu) means "Thank you very much" in polite speech, with ありがとう (arigatou) being the casual version. For apologies and getting attention, すみません (sumimasen) is remarkably versatile, functioning as "Excuse me," "I'm sorry," or even a light "Thank you" when someone has gone to trouble for you. A more direct apology is ごめんなさい (gomen nasai), with ごめん (gomen) being its casual form.
Introductions rely on two key phrases. はじめまして (hajimemashite), literally "for the first time," means "Nice to meet you" and is said when meeting someone for the first time. It typically leads into a self-introduction followed by よろしくおねがいします (yoroshiku onegaishimasu), which means "Please treat me well" or "Nice to meet you." Around meals, いただきます (itadakimasu) is said before eating to express gratitude for the food, and ごちそうさまでした (gochisousama deshita) is said after finishing. At home, the daily exchange いってきます ("I'm off") and いってらっしゃい ("Take care" or "See you later") bookend departures, while ただいま ("I'm home") and おかえりなさい ("Welcome home") greet arrivals.