What are CMM and CMMI? What is the difference?

The Capability Maturity Model for Software (CMM or SW-CMM) is a model for judging the maturity of the software processes of an organization and for identifying the key practices that are required to increase the maturity of these processes.

The Capability Maturity Model Integration (CMMI) provides the guidance for improving your organization's processes and your ability to manage the development, acquisition, and maintenance of products and services. CMM Integration places proven practices into a structure that helps your organization assess its organizational maturity and process area capability, establish priorities for improvement, and guide the implementation of these improvements.

The new integrated model (CMMI) uses Process Areas (known as PAs) which are different to the previous model, and covers as well systems as software processes, rather than only software processes as in the SW-CMM.

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