Sales promotion is used to stimulate short-term purchases and build long-term relationships. There are three main types: consumer promotion which uses coupons and samples, trade promotion which offers prices off and free goods, and business/sales promotion like trade shows and sales contests. Developing an effective promotion program requires establishing objectives, choosing appropriate tools, determining the size, conditions, duration, distribution, timing, and budget. Implementation and evaluation ensures proper execution and assessment of the program's success.