(1) A set of descriptive and operational information associated with a requirement when the requirement is created. A requirement type serves as an outline for all requirements of the same type and is useful for classifying and grouping similar requirements in a project. Each requirement type has its own set of user-defined attributes.
(2) A categorization of requirements based on common characteristics and attributes. Sometime requirement types are based on the requirement source or area of effect for example, stakeholder need, feature, use case, supplementary requirement, documentation requirement, hardware requirement, software requirement, and so on. Requirements may also be categorized based on the dimension of software quality that they represent for example, FURPS+.