Data normalization is a process that structures databases to enhance efficiency, maintain consistency, and eliminate redundant data. It involves breaking down data into smaller, related tables to minimize repetition and simplify updates. Normalization helps prevent redundancy and maintain consistency in a database by following a set of rules called "normal forms". Data denormalization intentionally introduces redundancy into a database to improve read performance, speed up queries, and reduce computational overhead. Denormalization reduces the need for complex joins by storing related data in a single table or document. The choice between normalization and denormalization depends on the specific needs of your application, with normalization ideal for transactional systems and denormalization suitable for analytical workloads.