Before talking about Quality Management, it is critical to understand the definition of Quality,
The degree to which a product meets its requirements
End of the day, Quality is a measurement.
Moving on to Quality Management, it is all about creating policies and procedures that meet the project’s defined quality needs. The aim of Quality Management is to ensure that the specified approach to quality is implemented on the project
Below are the processes of Quality Management knowledge area,

Plan Quality Management
It is the process of identifying quality requirements/standards for the project/product and documenting how the project will demonstrate compliance
Manage Quality
This process was introduced in PMBOK 6 replacing Perform Quality Assurance. Manage Quality is the process of translating quality management plan into executable quality activities that incorporate the organization’s quality policies into the project
Control Quality
It is the process of monitoring and recording results of executing the quality activities to assess performance and recommend necessary changes
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