How would you define pegging in the context of Advanced Planning?

Pegging is a term used in Advanced Planning to describe the relationship between the receipt and the issue elements of a product within a location. Receipt elements are planning elements that increase the stock of a product, such as production orders, purchase orders, or stock transfers. Issue elements are planning elements that reduce thestock of a product, such as sales orders, planned independent requirements, or reservations. Pegging links the receipt and issue elements according to the bill-of-material structure of all related products and represents the material flow through all levels of production. Pegging enables the system to identify and display quantity and date/time problems, such as shortages or delays, and to forward scheduling changes to other dependent elements. Pegging also forms the basis for the availability check and the capacity check in Advanced Planning12.

References:

1: SAP Help Portal: Pegging

2: SAP S/4HANA Production Planning and Manufacturing Certification Guide, Chapter 4: Advanced Planning