It describes the development of software, from the beginning to end. Its purpose is to define the intermediate phases in order to validate the application development. Thus, to ensure that the software meets the requirements for the implementation and verification of development procedures: it ensures that the methods used are appropriate.
This programs are implemented due to the fact that it is very expensive to fix an error that are identified in the late implementation phase. The software life-cycle helps to identify the errors as soon as possible; this helps the developers, so they can focus on quality of the software.
