In East Asian cultures, 'O' means 'correct, possible, or good,' whereas Western cultures more commonly use a check mark (✓). The emoji originated in Japan, reflecting this East Asian culture.

Beyond just marking correct answers, it's widely used to give positive responses like 'I agree,' 'It's possible,' or 'Let's do it.' You can add ⭕ at the end of a message to convey your meaning concisely and clearly when setting up plans with friends or agreeing to a suggestion.