This emoji, which features the character '祝' (shuku) meaning 'to celebrate' inside a circle, originated in Japan. It's a symbol often seen in formal congratulatory messages or on gift money envelopes.

It gives a more formal and polite feeling than simply saying 'congrats.' This makes it appropriate for extending congratulations to elders or colleagues. You can also often spot it in social media posts from fans celebrating K-pop idols' birthdays or anniversaries.