After a Document Set content type has been added to a document library, you can use it to create new multi-document work products. Additionally, when you click the folder for a Document Set to open it, you are taken to a Welcome Page that you can use to manage the content in the Document Set.
A Document Set is a group of related documents that you can manage as a single entity. You can create a Document Set in a single step, and then define its characteristics and metadata.
SharePoint has been used, over the last 10+ years, mainly for two things: Intranet Portals & Document Management. In the past, I have shared my opinion about the state of the Intranet. The topic of Document Management, I haven’t touched in a while.