What is the role of relationships between tables in a relational database?

Relationships between tables in a relational database provide a logical connection of data, allowing efficient storage and retrieval of related records from different tables. They help avoid data duplication, ensure data integrity, and enable complex queries using JOIN to combine information from multiple tables. For example, a "one-to-many" relationship between the "Users" and "Orders" tables allows retrieving all orders of a specific user.