At this point, you know the possible activities, the
possible phases performed during the software development process. But there
this something that we still haven't discussed, which is
very important. And that is how should we put these
activities together to develop software? And this all comes
down to the concept of software process model. Also called
software lifecycle model. And what this is, is a
prescriptive model of what should happen from the very beginning
to the very end. Of a software development process. The
main function of the life cycle model is to determine
the order of the different activities so that we know
which activities should come first and which ones should follow. Another
important function of the life cycle model is to determine
the transition criteria between activities. So, when we can go from
one phase to the subsequent one. In other words, what
the model should describe is what should we do next and
how long should we continue to do it for each activity
in the model. Now lets see a few traditional software process
models. I will discuss them here at the high level and
then revisit some of these models in the different mini courses.