Six sigma isn't about quality for the sake of quality; it's about providing better value to customers, investors, and employees. Green belt training requires approximately 16 days of hands-on effort spread over a 3 - 5-month period. 

The term ‘Six Sigma’ is drawn from the statistical discipline ‘process capability studies. Sigma, represented by the Greek alphabet ‘σ’, stands for standard deviation from the ‘mean’. ‘Six Sigma’ represents six standard deviations from the ‘mean.’ 

A business process or a process is a group of tasks that lead to a specific service or product for customers. It can be visualized with a flowchart or a process matrix. Business processes are fundamental to every company’s performance and implement a business strategy. Understanding and optimizing the business process is the crux of six sigma. 

A business system is a group of business processes that combine to form one identifiable unit of business as a whole. It is composed of processes, which in turn are composed of sub-processes and which are further composed of individual tasks. 

Feedback received from the process is used for process control thus, specializing in the input and output of the process for data collection. Every sub-process or task act as an input to the next task or as an output for the previous one.