Notifications are platform-generated alerts delivered to a channel's subscribers or followers when new content is published, a live stream begins, or community posts are made. On YouTube, subscribers can choose to receive all notifications, personalized notifications, or none at all. A high notification opt-in rate is a strong indicator of genuine engagement — it means the audience is actively interested in staying up to date with a creator's content. Creators can increase notification rates by publishing consistently according to an upload schedule, using community posts, and building anticipation around upcoming content.