Project management is an approach to planning and guiding project processes from start to finish. According to the PMI (Project Management Institute), the processes are guided through five stages: initiation, planning, executing, controlling, and closing. The five stages described here are typical in waterfall based methodologies, where one stage follows the next, and is suitable for projects that have a fairly rigid scope.
Agile Project management is widely used to control the complex processes of software development projects, and although there are similar stages, each approach usually has timeboxed iterations. Agile and iterative project management methodologies include XP, Srum, Evo & UP.