In the Media library, content is categorized into folders based on its source. Each source represents an app such as iTunes or Aperture. Within a folder, there is a hierarchy of media groups that descend from a root group. Within each group is a list of media objects, or individual files. Each of these media objects can be referenced by several other groups. The hierarchy of groupings varies depending on the source.
To edit multiple files, click each thumbnail. If there are several files, click each thumbnail and edit the desired media file. You can also select multiple files at once and select Bulk Action for bulk editing. After you have made your changes, you can click Save. To remove multiple media items from the list, choose the delete button. Click the trash can icon to clear it. The trash can icon will be removed when you delete it. This is a good option for archiving media files.
The screen options tab allows you to select how many Media items you want to view per page. Double arrow boxes indicate multiple pages; single arrow boxes indicate one page. Click the Edit Metadata button to edit the metadata. Once you’re done, click Save and close the Screen Options window. You can also edit the metadata by typing in keywords or phrases. To enter a search query, enter the keywords or phrase you want to search. If you find nothing, you can click Cancel.