Final answer:
Denormalization is a technique used to improve database performance by combining tables and introducing redundancy to reduce the complexity of database queries.
Step-by-step explanation:
Denormalization is a database optimization technique used by database professionals in which the normalization principles are reversed, leading to the combination of tables to reduce the complexity of database queries. In normalization, data is typically stored in separate tables to reduce redundancy. However, this can result in extensive table joins, which might degrade performance. In contrast, denormalization intentionally introduces redundancy in a controlled manner to improve database performance. The technique can be especially useful for read-heavy databases where complex joins would otherwise slow down data retrieval.