This document discusses database marketing and how it has become necessary for large retail chains and banks due to their inability to know each customer individually. It covers customer databases, data warehousing, and data mining. Database marketing involves using computer technology to track customer transactions and profiles to communicate with customers individually. The document then discusses how RFM analysis can segment customers into groups based on recency, frequency, and monetary value of purchases to implement targeted marketing campaigns. Maintaining high customer loyalty and retention is important for business profits. Database marketing systems combine customer, transaction, and other data with data analytics to generate targeted marketing decisions and customer clusters. Both internal and external data are important for database marketing analysis.