Data normalization aims to achieve a structured format in database design by organizing data to reduce redundancy and improve integrity. This process involves dividing large tables into smaller, related tables and defining relationships between them. The ultimate goal is to ensure that each piece of data is stored only once, which helps in minimizing anomalies during insertions, updates, and deletions. By normalizing data, databases can operate more efficiently and support complex queries that yield accurate results while ensuring a consistent data structure.