Six sigma is a methodology for measuring quality that strives for near perfection. Six sigma is a data-driven, well disciplined approach and methodology for eliminating defects. 
Six sigma can be used in manufacturing industry to production to service industry for quality control. This methodology uses data-driven approach on process improvement and variation reduction.
The Six sigma has 2 sub methodologies:
1.DMAIC (Define, Measure, Analyze, Improve and Control)
2.DMADV (Define, Measure, Analyze, Design and Verify)
The companies implemented six sigma are: GE (General Electric) is one of the most successful company implementing six sigma and estimated benefits on the order of US$ 10 Billion during the first five year of implementation.
Six sigma improves the quality of the output of a process by identifying and eliminating defects and minimizing variation in business and manufacturing industry. This is basically a statistical analysis and solving the errors.
Companies are now implementing six sigma approach to improve their product quality and services as part of their continue improvements and scaling greater heights of their business model to increase revenue as well.
Six sigma focuses on 3 areas namely
- a) Customers
- b) Processes
- c) Employees
a)Customer :- Customer defines quality of the product or services.
b)Process:- In processing, the quality should be looked from the customers perspective.
c)Employee:- Companies should invest in training employees for quality control (six sigma) so that they can increase revenue by improving overall quality of the product or services.
Companies also provide incentives and learning opportunities to their employees.
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