What does it mean to be @mentioned?

An @mention is like a gentle tap on your shoulder—a way to get your attention in a channel conversation or chat. When someone @mentions you, you get a notification in your Activity feed, and you also see a number next to the channel or chat you were @mentioned in. Click the notification to go directly to the point in the conversation where they mentioned you.

If you ever feel a little overwhelmed by all your @mentions, you can always filter your Activity feed to help sort them out.

How do I @mention someone?

To @mention someone, just type @ in the compose box and select their name from the menu that appears. You can @mention with suggested people.

Check out this related post that reviews @mentions in a mobile experience.