@Mentioning People on the Board
To mention a board participant in a comment or chat, type @ followed by the collaborator’s first and surname, or just pick the right person from the list of suggestions that pops up when you start typing.
When you post mentions on the board, people you mentioned will get an instant browser notification, if they are online, or an email notification if they are not. Feel free to update notification settings in your profile if you don't want to receive emails when collaborators mention you.
You can also quickly notify every participant on the board — just type @board in comments or chat and everyone will get a browser or email notification.