Apache CouchDB
Apache CouchDB is an open-source, document-oriented NoSQL database that uses JSON for documents, JavaScript for MapReduce queries, and HTTP for an API. It is designed for distributed environments with a master-master replication model, allowing data to sync seamlessly across multiple servers and devices. CouchDB prioritizes availability and partition tolerance in the CAP theorem, making it suitable for offline-first applications and collaborative systems.
Developers should learn CouchDB when building applications that require offline capabilities, real-time synchronization, or collaborative features, such as mobile apps, IoT systems, or multi-user platforms. It is particularly useful in scenarios where data consistency can be eventually consistent, and its HTTP-based API simplifies integration with web technologies. Use cases include content management systems, distributed data stores, and applications needing conflict resolution in disconnected environments.