Promotions and coupons are site-aware. Site-awareness can be part of the condition or the offer. For example:
Site-aware condition: A customer who buys $100 worth of merchandise on a given site receives free shipping.
Site-aware offer: A customer who buys $100 worth of merchandise from one site receives a 15% discount on a related site.
Coupons can include site constraints that control which sites the coupons can be claimed on or the number of coupons that can be claimed per site. Coupon site constraints do not affect where the associated promotions are valid.
