Could you explain the concept of normal forms in databases?

Normal forms are a set of rules for organizing data in relational databases to minimize redundancy and prevent update anomalies.

Main normal forms:

1. First Normal Form (1NF) — all fields contain atomic (indivisible) values, no repeating groups.
2. Second Normal Form (2NF) — the table is in 1NF, and all non-key attributes depend fully on the entire composite key (if the key is composite).
3. Third Normal Form (3NF) — the table is in 2NF, and there are no transitive dependencies between non-key attributes.

Applying normal forms helps create more efficient and reliable data structures, facilitates their maintenance, and reduces the likelihood of errors.