Relational Databases are a type of structured database that stores and organizes data in tables related by common fields, and it is used widely in various industries to maintain robust data integrity. Coursera's Relational Databases catalogue helps you understand the key principles of these databases, how to design and administer them to meet business needs effectively. You'll learn to create, query and manipulate databases using SQL, understand normalization, transactions, indexing, and other advanced database concepts. Gain expertise in designing database schema, managing data redundancy and ensuring data security and integrity. This knowledge is crucial for roles such as database administrator, data analyst, and back-end developer among others.