A daytime greeting meaning 'hello' or 'good afternoon'. Usually written in kana; the written particle は is pronounced 'wa'.
こんにちは、久しぶりですね。
Hello — it's been a while.
散歩中に近所の人と『こんにちは』と挨拶した。
I greeted a neighbor with 'hello' while walking.
メールの冒頭に『こんにちは』と書いて送った。
I started the email with 'Hello' and sent it.