The Component group enables you to model the physical components of your system in a Component diagram.
A component is a piece of hardware or software that makes up the system; for example, a DLL or Web Server are Components that might be deployed on a Windows 2000 Server (Node). See the Deployment Diagram topic for an example of this.
The Component group contains elements related to the actual building of the system: the components that make up the system (such as ActiveX DLL's or Java beans), the Interfaces they expose and the dependencies between those elements.
To add an element to the current diagram, click on the required icon and drag it into position on the diagram. Set an element name and other properties as prompted.
To add a relationship, click on the required icon, then click on the start element in the diagram and drag to the end element.