it describe the environmental condition under which the solution remains effective or the qualities that system must have.that means requirement related to increase
Performance – for example: response time, throughput, utilization, static volumetric
Scalability, Capacity ,Availability,Reliability,Recoverability,Maintainability,Serviceability,Security,Regulatory,Manageability,Environmental,Data Integrity,Usability, Interoperability
example: swipe machine, printer etc