Pegging is being able to look at the detailed activity of a part to determine who or what is creating the demand, is it a customer order, a forecast, a planned order, open and or planned purchase order, etc. Pegging is done via the MPS activity screen.
As used in material requirements planning: displaying details on the sources of the gross requirements or allocations for a product.
Tracing the source of requirements in a materials plan, caused by dependent demand from an upper-level item, independent demand from a customer or interplant order, or to replenish a desired inventory stock level.