The document discusses normalization of databases. Initially, databases have issues like repetition, insertion, deletion, and updating anomalies due to redundant data. The document then explains the three normal forms - 1NF, 2NF, and 3NF. It provides an example of an initial unnormalized table being split into multiple tables in 1NF, 2NF and 3NF to remove anomalies and redundancy. While normalization reduces redundancy and improves integrity, it can negatively impact performance due to complex joins required between multiple tables.