Redis

Remote Dictionary Server is an open-source, in-memory data structure store used as a databaseDatabaseAn organized collection of data, typically stored electronically.
More About Database, cacheCacheA temporary storage location that stores frequently accessed data to reduce load times.
More About Cache, and message broker. It supports data structures such as strings, hashes, lists, sets, sorted sets, bitmaps, hyperloglogs, and geospatial indexes with radius queries.

Redis is often used as a cache because it stores data in memory, allowing for much faster access than traditional disk-based databases. It also supports persistence, meaning that data can be written to disk to prevent data loss in case of system failure.

Redis supports various operations, including CRUD operations, complex data structures, and advanced data manipulation. It also has a built-in Pub/Sub messaging system, which allows for sending and receiving messages between different processes. This makes it well-suited for real-time applications such as chats, notifications, and gaming.

Redis supports multiple data replication methods, from master-slave replication to multi-master replication with automatic partitioning (Redis Cluster), which provides high availability and scalability.

Redis is widely used in many large-scale production environments due to its high performancePerformanceRefers to how fast a website or web application loads and responds to user interactions.
More About Performance, ease of use, and flexibility. It is used in various fields such as e-commerce, financial services, gaming, real-time analytics, and many more.