Conformance to requirements or fitness for use. Quality can be defined through five principal approaches: (1) Transcendent quality is an ideal, a condition of excellence. (2) Product-based quality is based on a product attribute. (3) Userbased quality is fitness for use. (4) Manufacturing-based quality is conformance to requirements. (5) Value-based quality is the degree of excellence at an acceptable price. Also, quality has two major components: (a) quality of conformance–quality is defined by the absence of defects, and (b) quality of design–quality is measured by the degree of customer satisfaction with a product’s characteristics and features.