Packages are the key organizing elements for UML models. You can use packages as containers for elements, views (diagrams), and other packages. Packages provide a way for you to divide large diagrams and models into manageable subsets. You can think of the entire system as a single high-level package with all the models and elements in it.
When you create a new model, the UML Model Diagram template automatically creates a top package for the model. This package serves as the container for all the elements, packages, and diagrams you create as part of the model.
Create a new package from the Model Explorer
In the tree view, right-click the package you want to create the new package in, click New, and then click Package.
A new package icon is automatically added to the tree view and the UML Package Properties dialog box opens.
Create a new package from a diagram
In the tree view, double-click the icon for the diagram you want to add the package to.
The drawing page for the diagram appears.
From UML Static Structure, UML Use Case, UML Component, or UML Deployment, drag a package shape onto the drawing page.
An icon representing the package is added to the tree view.
Create a new diagram from a package
To automatically create a new diagram each time you add a new package to your model, on the UML menu click Options, and then, on the UML Add-In tab, select Create a diagram page when a package or subsystem shape is added to a document.
To create a new diagram if this option is not selected, right-click the new Package shape and click Diagrams, and then click New. Type a name for the diagram and select a diagram type, and then click OK.
Add elements to a package
In the tree view, right-click the package you want to add elements to, click New, and then choose the type of element you want to add.
An icon for the element is added to the tree view.
Represent package contents in a diagram
In the tree view, right-click the icon for the package with contents you want to represent, and then choose the type of diagram you want to include in the package.
The appropriate stencil and a blank drawing page appear. A watermark with the name of the diagram type appears on the workspace.
Drag shapes representing the elements you want to include in the package onto the drawing page.