Explain the principle of data organization in a database to minimize duplication and ensure integrity.

Normalization is used in databases to minimize data duplication and ensure integrity. It involves organizing data into tables so that:

• Each table contains data about a single type of entity.
• Data redundancy is eliminated so that the same value is not stored in multiple places.
• Referential integrity between tables is maintained through keys (primary and foreign keys).

For example, instead of storing information about clients and their orders in one table with repeating client data, separate tables "Clients" and "Orders" are created, linked by the client key.

This simplifies data updates (changes in one place), reduces the likelihood of errors, and improves storage efficiency.

In Node.js, ORM or drivers are typically used to work with databases, which help implement such structures and maintain data integrity.