The Layout view displays layout data sets and members that you have added in a tree-style directory. Use this view to manage your layouts and apply them to the data sets and members you are working with.
More information:
View Types
Directory List View
Editor View
Selection View
Properties View
Report View
Layouts
Add a Layout
Create a Custom Layout
Modify Layout Rules
Define Selection Conditions
Insert a Layout
View a Layout
Update a Layout
Remove a Layout