The Work Breakdown Structure and the Work Breakdown Structure Dictionary decompose the product and the processes that construct the process into a “well formed” tree. The terminal nodes of the WBS tree are where Work Packages are defined. Work Packages are were cost are collected and Earned Value Management measurement is performed.
The Work Breakdown Structure definition starts with a clip from MIL-HDBK-881A.
There "may" be other definitions of a WBS. Some other project management document, some constructed from personal definitions. I'd suggest starting with this one and not moving away from this one unless there is a very very good reasons - and there really isn't one.
The WBS Dictionary goes with the WBS. A WBS Dictionary looks like this and states what the product (or component) looks like with the Work Package or Task is DONE. In this case the ARH Helicopter Crew Station cockpit elements.
Next comes the definition of the Functional Organization - The Organizational Breakdown Structure (OBS). This is a "well formed" tree of the people working on the project. The focus on the project is the only place to go for this. Not the firm, the other people in your department. Just the project.
The intersection of the People and the Product is shown in a Responsibility Assignment Matrix. The intersection of "what is the be built" and "who is to build it."
- The intersection of people and product defines a "single point of integrative responsibility." The "single" person who can answer questions about what's going on. Sure in a self organizing team, this can be a collective voice, by the single named person is where it starts.
- The Control Account says its name. It is a Point of Control for requirements, funding, and performance measurement.
- The Control Account Manager (CAM) is the title of the person "managing the control account," in our defense and space business. Inside the Control Account are Work Packages that contain Tasks for the work. This progressive decomposition provides visibility into all the aspects of the project
By The Way, you always want a title on your card that has a Verb. You "do" something. Control Account Manager is a verb - she manages Control Account.