What is Six Sigma ?

Six Sigma Evolution : A process improvement methodology that systematically improves the process. It was originally formulated at Motorola in 1986.It came into picture because, during 80's Motorola was consistently beaten by its competitor as they were not able to produce quality goods.While its competitor were able to deliver quality goods at respective cheaper price.So,the Motorola's CEO at that time,Bob Galvin tried to find out the bottleneck in their process and started a process improvement plan using six sigma methodology.

What is Six Sigma : It is process improvement methodolgy that systematically improves the process and produces the output within the specified specifications.
There are basically two methodology, one is DMAIC and the other is DMADV.

Sigma Levels : Achieving Six Sigma level of quality means that the product does not have more than 3.4 defects / million opportunities (3.4 DPMO). In IT, this may not be easily achievable and the Six Sigma projects in IT industry focus on reaching around 4 to 5 Sigma levels.

DMAIC :It is used to improve an existing process.It has five phases- Define, Measure,Analyze,Improve,Control.

Define:In Define phase,the team decides their improvement goals and finds out the problem in the current process.In this phase team comes up with a high level map of the process i.e. SIPOC,list of what is important to customer i.e. CTQ,list of customer needs i.e. CTP.

Measure:This phase finds out the all factors in the current process level and collects the datas which are very useful to the project.This phase also finds out the current sigma level of the project.

Analyze:This phaase determines the causes of the problem that needs improvement.After finding the causes,this phase finds out the way to eliminate those causes.

Improve:This phase identifies,evaluate and select the right improvement solutions.

Control:In Control phase,the team ensures that any variance is correct before they turn up defect.The team implements the Control Plan to ensure the continuous improvement of the process.

Roles in Six Sigma:The roles terminology of Six Sigma totally gives an impression of martial arts.
Six Sigma has several key roles like Executive Leadership,Champions,Master Black Belts,Experts,Black Belts,Green Belts,Yellow Belts and last is White Belt.

Other Quality Management Methodologies:There are many quality management methodologies other than Six Sigma.They are Quality Control,Total Quality Management,Zero Defects etc.