Poka-yoke is a Japanese term that means "mistake-proofing" avoiding (yokeru) inadvertent errors ((poka)) is a behavior-shaping constraint, or a method of preventing errors by putting limits on how an operation can be performed in order to force the correct completion of the operation. Poka-yoke either can prevent, or control, the wrong action.

It is suggested that the choice between these two should be made based on the behaviors in the process, occasional errors may warrant warnings whereas frequent errors, or those impossible to correct, may warrant a control poka-yoke. Poke Yoke systems have two main purposes:

Prediction - Catch a defect that is about to occur.

Detection - Catch a defect that has already occurred. While there are three Basic Functions of a Mistake proofing device. 

Control - Removal of defect from system.

Warning - A signal to attract attention to defects.  Shutdown - A restricting tool to stop the process when a defect occurs.