3.1 Use Case View
Use Case view includes all the actors, use cases and Use Case diagrams in the system. It might include some Sequence and Collaboration diagrams. The Use Case view is an implementation-independent look at the system. It focuses on a high-level picture of what the system will do, without worrying about the details of how will do it.
Use Case view中包含系统中所有的参与者、用例和用例图。也可以包含一些时序图和协作图。Use Case view在系统中可以看成是一个独立的实现，它侧重用高级别的视图表明系统做什么，而不用考虑具体的实现。
3.2 Logical View
Logical view focuses on how the system will implement the behavior in the use cases. It provides a detailed picture of the pieces of the system, and describes how the pieces interrelate. The Logical view includes among other things the specific classes that will be needed, the Class diagrams and the State transition diagrams. With these detailed elements, developers can construct a detailed design for the system.
Logical view重点描述在系统中如何实现用例。它提供系统各模块的详细视图，并描述这些模块之间的关系。Logical view 包含队特殊类之外的类图还有状态转换图。通过这些具体的元素，开发者可以对系统构建具体的设计。
3.3 Component view
Component view contains information about the code libraries, executable files, runtime libraries and other components in your model. A component is a physical module of code.
Component view包含的信息有代码库、可执行文件、运行时库，还有在你模型中的其他组件。一个组件就是一个物理的编码模块。
3.4 Deployment view
Deployment view is concerned with the physical deployment of the system, which may differ from the logical architecture of the system.
Deployment view关于系统的物理发布，它不同于系统的逻辑架构。
