What is the channel area?
The channel area is a tree structure that controls which assets are available for which products and to which users and/or groups.
Publishing to products
Publishing in DAM Centers from version 4.7.0 and above, is different than previous versions' way of publishing.*
Assets will be published when you set two specific metadata fields from either the DAM Center, the Media Manager or the DAM for Sitecore. The two fields are "Rights management" and "Availability".
Removing all entries for one or both of the metadata fields, will automatically unpublish the asset from all channels.
Rights for users and/or groups on folders (Rights management)
There are two states an asset can be published in; public and internal. The public state will make the asset available for each and everyone accessing your chosen product, while the internal state by default will be available for the users "Light user", "Content Creator", "Administrator", and "Super Administrator".
Products of which assets should be available from (Availability)
There are three products (aka. availabilities) that assets can be published to; Media Manager, Office Connector, and DAM for Sitecore. The Media Manager and DAM for Sitecore both need to be installed in order to appear as options in your "Availability" list.
Admin rights
When you have an asset that is not published to any channel folder, it will still be available to you in the Media Manager if you login with either Administrator, Super administrator or the Content Creator user that has uploaded the asset in the first place. All other users will not be able to see or edit the asset, including all other Content Creators that did not upload the asset.
When the asset is only available in the Media Manager for the previously mentioned users, the asset isn't regarded as having been published. This feature has been made, so that you'll be able to use the Media Manager as a front end, instead of using the DAM Center for publishing unpublished assets every time.
The assets that are published will have a red padlock icon in them in the Media Manager, whereas the published assets (internal and public) will have none + are shareable and downloadable. (See images below)