A package is a grouping of model elements and is represented by a symbol that looks like a manila file folder . You can imagine an entire system description as a package with all the system elements in it, including other packages, models, diagrams, and elements.
A package is the basic organizing element of a UML model. Each element belongs to only one package, and one package can be nested in another. You can create new packages or add elements or views (diagrams) to packages by right-clicking icons in the tree view.
Dropping a Package shape onto a drawing page automatically creates a new static structure diagram on a new page. (Double-click the new static structure element in the tree view to go to that page.) To create a view, you can drag some of the elements that belong to the package onto the new page.
Name a Package shape and add other property values
Double-click the shape.
Control which property values are displayed on the Package shape
Right-click the shape on the drawing page, click Shape Display Options, and then select or clear options to show or hide values.
Create a diagram within a Package shape
Right-click the shape on the drawing page, and then click Diagrams. Click New, select the diagram type you want, click OK, and then click OK again.
Open a diagram contained in a Package shape
Right-click the shape on the drawing page, and then click Diagrams. Select the diagram you want, and then click OK.
Navigate to other views of the Package shape
Right-click the shape on the drawing page, and then click Views. Select the view you want, and then click OK.
Show, in a view, the relationships between the package and other elements
Right-click the Package shape on the drawing page, and then click ShowRelationships.