Invite-only channels are closed channels that allow members to join only through invites. If the organization and team channels are open, anyone from the organization or team can join. But what if you want to build a secure place that only certain members can access, where you can also approve and select who can join? The Invite Only channels come into play at this point.
To check your Invite only channels, click Channels in the left-sidebar. Invite only channels are distinguished from other team channels by a lock icon.

Admin Note :
You can set up your channel with permissions on who should send messages, edit info, add or remove participants, and so on. If you are an admin, you have access to make changes. However, you can also choose who the permissions are given to - an admin, a moderator, or a member.
To give permissions and configure settings:
- Click the Channel icon.
- Under Permissions, you will find Configuration and Permissions.
- Select the changes you need to make.
- The changes will be immediately reflected.
Consider the following example:
ZylkerMobile App team has an invite only channel #marketing where only the marketers handling mobile application marketing activities have access.