The top level packages in a model (below the model root node) are created as Views. Views are used simply to subdivide the model into partitions such as Business Process, Logical View or Dynamic View. They are a good way to extend the model depending on specific requirements and modeling techniques.
There are 6 main types of View, each with their own package icon:
- Use Case View - eg. Use Case diagram, Analysis diagram, Robustness diagram
- Dynamic View - eg. Activity diagram, Communication diagram, Sequence diagram, State diagram
- Class View - eg. Class Model, Code Engineering, Data Model
- Component View - eg. Component diagram
- Deployment View - eg. Deployment diagram
- Simple View
You can use the first five categories or devise your own based on the Simple View. You can create Views, rename them, move them into a different order, or delete them. Do this by right-clicking the mouse on the selected View to open the context menu, and choose the appropriate option.