  Software has been playing a key role in the development of modern society.
Software industry has an option to choose suitable methodology/process model
for its current needs to provide solutions to give problems. Though some
companies have their own customized methodology for developing their software
but majority agrees that software methodologies fall under two categories that
are heavyweight and lightweight. Heavyweight methodologies (Waterfall Model,
Spiral Model) are also known as the traditional methodologies, and their
focuses are detailed documentation, inclusive planning, and extroverted design.
Lightweight methodologies (XP, SCRUM) are, referred as agile methodologies.
Light weight methodologies focused mainly on short iterative cycles, and rely
on the knowledge within a team. The aim of this paper is to describe the
characteristics of popular heavyweight and lightweight methodologies that are
widely practiced in software industries. We have discussed the strengths and
weakness of the selected models. Further we have discussed the strengths and
weakness between the two opponent methodologies and some criteria is also
illustrated that help project managers for the selection of suitable model for
their projects.
