Each phase is defined by activities, deliverables, and checkpoints. Product Requirements Product requirements encompass a list of high level features or capabilities that the business team has committed to delivering to a customer. Product requirements do not specify how the features or capabilities will be designed. Project requirements are the deliverables and checkpoint approvals required during each phase of development. These requirements are those which the design team must adhere to in order to develop the product, not general product or user requirements.
Prototypes are product models that are used to represent, test, and iterate current design concepts.
Prototypes can represent use models, task scenarios, and user interfaces and can be developed on a number of platforms including index cards, paper and pencil mockups, and functional and non- functional computer models. Prototypes can be useful at many points during design, such as initial concept development, heuristic evaluations, and usability testing. A task is a set of physical and cognitive procedures that when combined serve to achieve a particular goal. A task flow is a written or graphical representation of the interrelationships between tasks, particularly with regard to order of performance. Task flows often include information about the procedures, events, or items required to accomplish each task goal.