it is necessary that your system is able to record and store each of the transactions of your customers. Information such as, amount of purchases, total amount of purchases by time periods, items and/or services purchased, frequency, responses to promotions made by your company, type of responses for each invitation to participate in promotions; Apart from all that basic information about your customers, such as demographic data, geographic, and market specific information, such as the type and characteristics of the products and services you offer.