A hub is a collection of Releases. Artists typically use Hubs as their profile page. Labels typically use Hubs as their catalog page. Listeners typically use Hubs as playlists and collections. You can upload releases through or repost releases to a Hub.
Uploading to a hub adds another layer of context to a release by signifying its origin—the name of the hub will appear in blue under your release. If you have multiple hubs, please select the hub that you wish to upload to when creating your release.
Reposting allows you to curate releases that you did not upload. For instance, if a label uploads an artist's release through the label's hub, the artist can repost it to their own hub. This allows the release to live on different pages across Nina. A listener could also repost the release into a playlist they're making.
You can manage Hubs independently or add collaborators via your hubs settings. If you're a label, in a band, or building playlists with friends, inviting collaborators allows whoever you add to be able to upload through or repost to your Hub. There is no limit on how many Hubs you can make.
You can read more about the inspiration behind hubs here.