Packages
A package partitions the domain studied and the associated work. It enables grouping of various elements, in particular use cases and classes. A package can also contain other packages. Packages are interconnected through contractual reports defining their interface.Examples of package: the commercial information system, accounting, production management, digital control of a machine, an alarm system, etc.
You can create a package using the Package 
button in the toolbar. You can then increase its size in order to place use cases within it.
button in the toolbar. You can then increase its size in order to place use cases within it.You can link a use case to a package simply by placing it within the package. When you have moved the object within the package, the package shape is highlighted to indicate that the object will be connected to it
