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Introduction to Redis

Redis is the world’s fastest in-memory database. It provides cloud and on-prem solutions for caching, vector search, and NoSQL databases that seamlessly fit into any tech stack—making it simple for digital customers to build, scale, and deploy the fast apps our world runs on.

To use Redis, you can choose between the Redis Source Available License 2.0 (RSALv2) or the Server Side Public License v1 (SSPLv1).

Redis provides data structures such as stringshasheslistssetssorted sets with range queries, bitmapshyperloglogsgeospatial indexes, and streams. Redis has built-in replicationLua scriptingLRU evictiontransactions, and different levels of on-disk persistence, and provides high availability via Redis Sentinel and automatic partitioning with Redis Cluster.

You can run atomic operations on these types, like appending to a stringincrementing the value in a hashpushing an element to a listcomputing set intersectionunion and difference; or getting the member with highest ranking in a sorted set.

To achieve top performance, Redis works with an in-memory dataset. Depending on your use case, Redis can persist your data either by periodically dumping the dataset to disk or by appending each command to a disk-based log. You can also disable persistence if you just need a feature-rich, networked, in-memory cache.

Redis supports asynchronous replication, with fast non-blocking synchronization and auto-reconnection with partial resynchronization on net split.

Redis also includes:

You can use Redis from most programming languages.

Redis is written in ANSI C and works on most POSIX systems like Linux, *BSD, and Mac OS X, without external dependencies. Linux and OS X are the two operating systems where Redis is developed and tested the most, and we recommend using Linux for deployment. Redis may work in Solaris-derived systems like SmartOS, but support is best effort. There is no official support for Windows builds.


Redis release cycle — How are new versions of Redis released?

Redis license — Redis license and trademark information

Redis Enterprise — Learn about Redis Enterprise

About Redis Stack — Learn more about Redis Stack