@Mentions call attention to your message.
In a chat or channel conversation, type @, followed by your teammate’s name or email address, and select them.
They’ll get a notification in their Activity feed about the conversation.
Desktop
To get someone’s attention in a channel conversation or a chat, @mention them. Just type @ before their name and then select them from the menu that appears.
Note: You can also mention someone simply by typing their name. Start by capitalizing the first letter and as you continue to type the name, a list of people will show for you to choose from.
They receive a notification, which they can click to go directly into the point in the conversation where they were mentioned.
To get the attention of an entire team, try one of these:
- Post something in the Team’s general channel. The channel name appears bold for every team member.
- Type @team to message everyone on that team.
- Type @channel to notify everyone who has favorited that channel.
FYI, a team owner needs to enable these features.
Mobile
To get someone’s attention in a channel conversation or a chat, @mention them. Just type @ before their name and then select them from the menu that appears.
They receive a notification, which they can click to go directly into the point in the conversation where they were mentioned.
To get the attention of an entire team, try one of these:
- Post something in the Team’s general channel. The channel name appears bold for every team member.
- Type @team to message everyone on that team.
- Type @channel to notify everyone who has favorited that channel.
FYI, a team owner needs to enable these features.
Source: Microsoft