Explain Quality Control.

Quality Control: Control is a system for measuring and inspecting (checking) a phenomenon.  This suggests when to inspect, how often to inspect and how much to check.  In addition, this incorporates a feedback mechanism that explores the causes of poor quality and takes corrective action. This quality control system performs inspection, analysis and testing to conclude whether the quality of each product is according laid down quality standards or not. It is termed as statistical quality control if statistical techniques are employed to control quality or to resolve quality control problems.