Azure SQL is a fully managed relational database service provided by Microsoft Azure. It allows for the creation, management, and scaling of SQL databases in the cloud. Azure SQL supports engines like SQL Server, MySQL, and PostgreSQL, making it a flexible solution for traditional relational workloads. It uses a predefined schema and provides strong consistency, ideal for applications requiring complex queries and ACID transactions. Cosmos DB is a globally distributed, multi-model NoSQL database service. It supports various data models like key-value, document, graph, and column-family, providing a flexible schema design. Cosmos DB offers low-latency, high-throughput, and can scale horizontally with automatic partitioning, making it suitable for globally distributed applications, real-time analytics, and use cases like IoT, gaming, and microservices..