Konnichiwa means "Hello" or "Good afternoon." This is a general greeting used during the daytime, usually from late morning until early evening. It's versatile and can be used in most situations, formal or informal. For instance, you can say "こんにちは" when entering a shop.

昼間（午前中から夕方まで）に使う、一般的な挨拶です。誰にでも使えます。「こんにちは！」