Quality Control (QC) is a single inspection to ensure that a finished product meets the quality criteria set by Quality Assurance
or the customer's requirements. The difference between quality control and quality assurance (QA) lies in the time period in which the tests take place. While Quality Assurance starts before the production of the products, thus proactively establishes the level of quality, Quality Control takes place reactively and refers to confirmation that certain requirements have been met by a product or service. That is, on the manufactured product. Moreover, quality control is about quality inspection of single items or randomly selected single items. Quality control can be used in all stages of production of goods, products, services, and software
, as well as in the receiving and shipping of goods. As for the procedure of quality control, the specific standards that the product must meet are determined in advance of the inspection. Then, the scope and corrective actions are determined. It also involves how to deal with products that do not meet the quality standards or are defective. If many products deviate from the quality standard, the production process must be revised.