Redis

Redis is a fast, open-source, in-memory key-value store built for low-latency and high-throughput workloads. It’s widely used for caching, real-time analytics, session storage, and pub/sub messaging.As a leading alternative to traditional databases and caching systems like Memcached, Cassandra, and KeyDB, Redis supports rich data types and advanced operations suited for modern application architectures.

Key features include:

• In-memory storage with optional persistence (RDB, AOF)
• Advanced data structures: lists, sets, streams, geospatial, and more
• Built-in replication, clustering, and failover via Redis Sentinel
• Support for custom modules and Lua scripting
• Sub-millisecond performance for real-time systems

Use cases include:

• Application-level caching and performance optimization
• Session storage for web and mobile applications
• Real-time pub/sub messaging in chat or notification services
• Leaderboards, analytics dashboards, and traffic monitoring
• Geospatial data querying and event stream processing