You can Refresh or Update Libraries to bring them up-to-date.
A Refresh is something you'll want to do less often and so it's a manual action.
In many cases, Updates may be initiated for you automatically such as when you save changes to a Library's settings.
Once a Library has been created, it is processed by your Plex Media Server so all the media items are matched and metadata is gathered.
As time goes on, you'll add and remove media to the Libraries or make other changes that mean the Library is no longer up-to-date.
You can think of refreshing as "update metadata for the requested item even if it already has some".You should refresh a Library or individual item if: Tip!