Abstract :
Obtaining quality documentation is one of the most difficult jobs in the analysis, design and development of a data processing system. Most DP systems require three types of documentation before a system becomes operational. These three types are the results of three evolutionary phases in the installation of a given system. Figure 1 depicts the evolutionary phases and defines the three types of documentation required. Actually, there are four phases and four types of documentation in the life of a system. The fourth phase is the System Maintenance Period of an ongoing system, and the fourth type of documentation is the User Reference Documentation.