Each Team is created with a General channel.

By default everyone can post in this channel.

Now you can define with 3 different levels who can post in this channel:

  • Everyone can post (the default setting)
  • Everyone and display an alert that everyone in the Teams will be notified
  • Just the Teams owner

To define this setting, you need to go (as the Team owner) to the Team settings (Manage Team) and then access the Permissions options

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Below the notification if you choose the second option (Everyone can post but display a notification); you can see how many user will see your post

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