Quality Control vs Quality Assurance

Quality Assurance is process oriented and focuses on defect prevention; while quality control is product oriented and focuses on defect identification.

Comparison chart

Improve this chart	Quality Assurance	Quality Control
Definition:	QA is a set of activities for ensuring quality in the processes by which products are developed.	QC is a set of activities for ensuring quality in products. The activitiesfocus on identifying defects in the actual products produced.
Focus on:	QA aims to prevent defects with a focus on the process used to makethe product. It is a proactive quality process.	QC aims to identify (and correct) defects in the finished product.Quality control, therefore, is a reactive process.
Goal:	The goal of QA is to improve development and test processes so that defects do not arise when the product is being developed.	The goal of QC is to identify defects after a product is developed and before it's released.
Statistical Techniques:	Statistical Tools & Techniques can be applied in both QA & QC. When they are applied to processes(process inputs & operational parameters), they are calledStatistical Process Control (SPC); & it becomes the part of QA.	When statistical tools & techniques are applied to finished products (process outputs), they are called as Statistical Quality Control (SQC) & comes under QC.
What:	Prevention of quality problems through planned and systematicactivities including documentation.	The activities or techniques used to achieve and maintain the productquality, process and service.
How:	Establish a good quality management system and the assessment of its adequacy & conformance audit of the operation system & the review of the systemitself.	Finding & eliminating sources of quality problems through tools & equipment so that customer's requirements are continually met.
Example:	Verification is an example of QA	Validation/Software Testing is anexample of QC
Responsibility:	Everyone on the team involved indeveloping the product is responsible for quality assurance.	Quality control is usually the responsibility of a specific team that tests the product for defects.
As a Tool:	QA is a managerial tool	QC is a corective tool

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