A Tag is a special index that groups documents within or between applications by storing a common keyword in a free-form index field. The ability to add, view, or modify Tags is managed by an application-level permission.
For example, a user may want to have a meeting regarding a subset of documents that are not linked by common index field. A meeting organizer can Tag each document with a common keyword and notify other members in a meeting to perform a Tag search with this keyword.
Users can now view all of their documents with one quick glance versus performing multiple searches across all applications to identify the documents pertinent to the meeting.