Sales promotion is used as an incentive to encourage customers to purchase a product. It aims to stimulate immediate sales and can include discounts, coupons, gifts, and sweepstakes with a limited time offer. There are internal reasons like meeting sales targets and external reasons like increasing competition that lead companies to spend more on sales promotions. Promotions can be targeted at retailers through trade promotions like discounts or at consumers directly. The effectiveness of promotions may decline over time due to costs and clutter, so novelty is important.