The Item Discounts tab allows items configured with validation templates (Action tab > Validation section) to be “assigned” to the pass; this allows various discount macros to be configured per “assigned” item. This creates the ability for the same pass type to validate many different items (validation products) and execute different actions based on the item being validated. Typically, this involves variable discounting (varying application of different specials) based on the item being validated. See Validation with a DCI (validation template) and validation products for more details.