What are the control charts in management?

Control Charts:

These charts are based upon statistical sampling theory, as per that an enough sized sample drawn, at various from a lot, shows the lot. All processes whether automatic or semiautomatic are susceptible to variations that in turn, result within changes in dimensions of the products. Such variations happen either because of chance causes or because of certain factors to that we can assign the causes for such variations. Variation within the diameter of spindles being manufactured onto lathe may be either because of tool wear, non-homogeneity of bar stock, modifies in machine setting, and so on. The concept of control chart is to detect such changes in dimensions and indicate when the component parts being manufactured are into the given tolerance or not.