To provide a basis for understanding the structure and organization of the
design of the system, an architectural view called the Logical View
is used in the Analysis & Design workflow. There is only one logical view of
the system, which illustrates the key use-case realizations, subsystems,
packages and classes that encompass architecturally significant behavior. The
logical view is refined during each iteration.
The logical view shows an architecturally significant
subset of the design model;
i.e. a subset of the classes, subsystems and
packages, and use-case realizations.
There are two additional views, the Use-Case View (handled
in the Requirements workflow) and the Implementation View, handled
in the Analysis & Design, and Implementation workflows.
The architectural views are documented in a Software Architecture
So in essence, architectural views can be seen as abstractions or
simplifications of the models built, in which you make important characteristics
more visible by leaving the details aside. The architecture is an important
means for increasing the quality of any model built during system development.