Each item or portfolio may have a phase, or a sequence of phases, defined as the item's life cycle. Examples of phases could be requirement analysis, design, coding and so on. Each phase may have one or more deliverables that must be completed before you can progress to the next phase.
In PPM, life cycles are defined once and then used for many different items. In the same way, phases can be defined once and then used in different life cycles.
To define item life cycles, complete the steps in Creating Phases and Creating Life Cycles.