WHAT: Collections are temporary folders that contain only references to original files, and not the files themselves. As such, you will never see a blue pin on a file in a collection.
Collections offer a flexible way to gather and preview collections of ideas, without handling or moving any original files. A collection can be thought of a ‘lightbox’.
WHY: A file can be included in multiple collections, without the need to create copies of it, or move it from the folder or space in which it is located. Collections reduce storage requirements in a Chorus site and make it easy to gather files together for specific projects, without disturbing the source folders.