What are dynamic actions? Where do you configure them?

Dynamic Actions are automatically trigerred by the system when certain actions met. Eg: If you enter no of Child as 2 in IT0002, the system automically triggers the IT0021, subtype Child to enter the details, Otherwise it wont trigger the IT0021, if you didnt mention any value in no of child in IT0002. Same like that we can configure Dynamic Actions depends on our need using the path IMG->PM->PA-> Customizing Procedure -> Dyn Action. or by using Table T588Z.