According to ISO 9000:2005 (3.1.1), the definition of quality is degree to which a set of inherent characteristics (3.5.1) fulfills requirements (3.1.2)
There are 8 principles of Quality Management;
Quality Management (3.2.8) can be defined as coordinated activities to direct and control an organization (3.3.1) with regard to quality (3.1.1)
Quality Planning (3.2.9) is part of quality management (3.2.8) focused on setting quality objectives (3.2.5) and specifying necessary operational processes (3.4.1) and related resources to fulfill the quality objectives
Quality Control (3.2.10) is part of quality management (3.2.8) focused on fulfilling quality requirements
Quality Assurances (3.2.11) is part of quality management (3.2.8) focused on providing confidence that quality requirements will be fulfilled.
Quality improvement (3.2.12) is part of quality management (3.2.8) focused in increasing the ability to fulfill quality requirements.