1. In management, an action item is a documented event, task, activity, or action that needs to take place. Action items are discrete units that can be handled by a single person.
2. A short term goal that requires a defined measure of work to complete. Basically a dynamic, proactive version of your to do list.
Collective amount, sum, or mass arrived-at by adding or putting together all components, elements, or parts of an assemblage or group, without implying that the resulting total is whole (contains everything that should be in it).
Agile software development is a group of software development methods in which solutions evolve through collaboration between self-organizing, cross-functional teams. It promotes adaptive planning, evolutionary development, early delivery, continuous improvement, and encourages rapid and flexible response to change.