When someone likes or comments on a page or a news post you created, or mentions you using @, you will be notified by email. When someone replies to a comment on a page or a news post, the commenter will also be notified.
Note: Some functionality is introduced gradually to organizations that have opted in to the Targeted Release program. This means that you may not yet see this feature or it may look different than what is described in the help articles.
Notification emails for comments and comment replies are batched together, while notifications for likes are batched together. Additionally, @mention notifications are batched separately.