Azure Cosmos DB supports multiple application programming interfaces (APIs) that enable developers to use the programming semantics of many common kinds of data store to work with data in a Cosmos DB database. The internal data structure is abstracted, enabling developers to use Cosmos DB to store and query data using APIs with which they're already familiar.
When to use Cosmos DB
Cosmos DB is a highly scalable database management system. Cosmos DB automatically allocates space in a container for your partitions, and each partition can grow up to 10 GB in size. Indexes are created and maintained automatically. There's virtually no administrative overhead.
Cosmos DB is a foundational service in Azure. Cosmos DB has been used by many of Microsoft's products for mission critical applications at global scale, including Skype, Xbox, Microsoft 365, Azure, and many others. Cosmos DB is highly suitable for the following scenarios:
Retail and marketing. Microsoft uses Cosmos DB for its own e-commerce platforms that run as part of Windows Store and Xbox Live. It's also used in the retail industry for storing catalog data and for event sourcing in order processing pipelines.
Gaming. The database tier is a crucial component of gaming applications. Modern games perform graphical processing on mobile/console clients, but rely on the cloud to deliver customized and personalized content like in-game stats, social media integration, and high-score leaderboards.
IoT and telematics. These systems typically ingest large amounts of data in frequent bursts of activity. Cosmos DB can accept and store this information quickly.
Web and mobile applications. Azure Cosmos DB is commonly used within web and mobile applications, and is well suited for modeling social interactions, integrating with third-party services, and for building rich personalized experiences.