CMMI Basics

Process Categories

Management, Organizational, Engineering
Organization's standard software process
An organization's standard software process is the operational definition of the basic process that guides the establishment of a common software process across the software projects in the organization. It describes the fundamental software process elements that each software project is expected to incorporate into its defined software process. It also describes the relationships (e.g., ordering and interfaces) between these software process elements. It guides the establishment of a common software process across the software development and maintenance projects in the organization.

Software process architecture
The software process architecture is a high-level (i.e., summary) description of the organization's standard software process. It describes the ordering, interfaces, interdependencies, and other relationships between the software process elements of the organization's standard software process. It also describes the interfaces, dependencies, and other relationships to other external processes (e.g., system engineering, hardware engineering, and contract management).

Software process element
A software process element is a constituent element of a software process description. Each process element covers a well-defined, bounded, closely related set of tasks (e.g., software estimating element, software design element, coding element, and peer review element). The descriptions of the process elements may be templates to be filled in, fragments to be completed, abstractions to be refined, or complete descriptions to be modified or used unmodified.

Software Life cycle
A software life cycle is the period of time that begins when a software product is conceived and ends when the software is no longer available for use. The software life cycle typically includes a concept stage, requirements stage, design stage, implementation stage, test stage, installation and checkout stage, operation and maintenance stage, and sometimes, retirement stage.
Because an organization may be producing software for a variety of contractual and/or commercial customers and users, one software life cycle may not be appropriate for all situations. Therefore, the organization may identify more than one software life cycle for use by the projects. These software life cycles are typically obtained from software engineering literature and may be modified for the organization. These software life cycles are available to be used, in combination with the organization's standard software process, in developing a project's defined software process.

Project's defined software process
The description of the project's defined software process is the operational definition of the software process used by the project. The project's defined software process is a well-characterized and understood software process, described in terms of software standards, procedures, tools, and methods. It is developed by tailoring the organization's standard software process to fit the specific characteristics of the project.
This tailoring includes selecting a software life cycle from those approved by the organization and modifying the organization's standard software process to fit the specific characteristics of the project.
The project's defined software process provides the basis for planning, performing, and improving the activities of the managers and technical staff performing the project's tasks and activities. It is possible for a project to have more than one defined software process (e.g., for the operational software and for the test support software) or to have one defined software process for two or more similar projects.

Stage
A stage is a partition of the software effort that is of a manageable size and that represents a meaningful and measurable set of related tasks which are performed by the project. A stage is usually considered a subdivision of a software life cycle and is often ended with a formal review prior to the onset of the following stage.

Task
The work to be performed is broken down into tasks. A task is a well-defined unit of work in the software process that provides management with a visible checkpoint into the status of the project. Tasks have readiness criteria (preconditions) and completion criteria (postconditions).
Within the context of process definition, a task is a well-defined component of a defined process. All tasks can be considered activities, but not all activities are well enough defined to be considered tasks (although an activity may include a task). Because of this, use of "task" in the Level 2 key practices is avoided and the less rigorous term "activity" is used.

Activity
An activity is any step taken or function performed, both mental and physical, toward achieving some objective. Activities include all the work the managers and technical staff do to perform the tasks of the project and organization.

Software work product
The results of activities and tasks primarily consist of software work products. A software work product is any artifact created as part of defining, maintaining, or using a software process, including process descriptions, plans, procedures, computer programs, and associated documentation, which may or may not be intended for delivery to a customer or end user. Work products become an input to the next step in the process or provide archival information on the software project for use in future projects.
Examples of software work products include plans, estimates, data on actual effort, corrective action documentation, and requirements documents. The subset of software work products that are deliverable to the customer or end user are referred to as software products.

Software product
The software products are the complete set, or any of the individual items of the set, of computer programs, procedures, and associated documentation and data designated for delivery to a customer or end user.
All software products are also software work products. A software work product that will not be delivered to a customer or end user is not, however, a software product.