X Bar S Control Charts are a type of control chart often used to examine the process mean and standard deviation over time.
X Bar R charts are the widely used control charts for variable data. They help to examine the process stability in many industries.
An XmR chart (aka Shewhart’s Control Chart aka ImR chart) is a chart where the control limits are calculated from the moving average range.
Control charts are a great tool to help determine if a process is under statistical control, the level and source of variation experienced.