work breakdown structure

An arrangement of work elements, and their relationship to each other and to the end product or service.

In the CMMI Product Suite, a useful result of a process. This can include files, documents, products, parts of a product, services, process descriptions, specifications, and invoices. A key distinction between a work product and a product component is that a work product is not necessarily part of the end product. (See also "product" and "product component.")
In CMMI models, the definition of "work product" includes services, however, the phrase "work products and services" is used to emphasize the inclusion of services in the discussion.

Characteristics of products, services, and project tasks used to help in estimating project work. These characteristics include items such as size, complexity, weight, form, fit, and function. They are typically used as one input to deriving other project and resource estimates (e.g., effort, cost, and schedule).