This part of GB/T 17989 gives the key elements and basic principles of the control chart method, and defines various control charts (including control charts related to conventional control charts, control charts emphasizing process acceptance or online process adjustment, and special control charts) . This section only gives the basic principles and concepts, and illustrates the relationship between various control chart methods to help select the most suitable control chart method in a specific situation. This section does not give the statistical control method used in the control chart, which is described in detail in other parts of GB/T 17989.