Collections can be used as a generic way of maintaining an ordered list of stories and other items. A collection can be an alternative way of grouping a number of items to supplement the primary position in the Storymap tree.
Collections can be described with a title and description, automatically accumulating effort and value estimates for all items in the collection. But putting items in a collection does not have any functional effect on the items. Any item can be in multiple collections at the same time.
Collections can be viewed and managed primarily from the Product Backlog view but also from the Storymap view.