In: Memo, Universitaet Dortmund, Facbereich Informatik, (1990), Report-Nr: 55., pages 1-12. 1990.
Abstract: Recent research efforts, including projects like ALF and ESF, indicate that models for software processes (SP) are regarded nowadays as one of the most essential but still missing parts of software development environments. Software process models (SPM) are used for describing communication between people involved in development, for finding mistakes, and for improving the development productivity and increasing the quality. The SP is the sequence of activities performed during the creation and evolution of a software system. It becomes obvious that there is one SP for each software system that is developed. An SPM describes general features of a class of SPs but not those features that are unique for each SP. Well-known examples for SPMs are the waterfall model, the spiral model, and prototyping models. SPMs describe which activities have to be performed at what time