Type @ and the first few letters of the person's name, pick them from the list, and then type and send your message.


 

By the way, if you want to get everyone’s attention, save yourself from typing everyone’s names. Just type @All when you want to share something really important with everyone in the space.


 

In a space where there are people with the same first part of their display name, when picked from the list, the full display name will be tagged in the message to avoid any confusion.