The Redis project began when Salvatore Sanfilippo, the original developer of Redis, was trying to improve the scalability of his Italian startup, developing a real-time web log analyzer. As of 2015 the project is sponsored by Redis Labs.
Redis is a fast, open-source, in-memory key-value data store for use as a database, cache, message broker, and queue. It supports different kinds of abstract data structures, such as strings, lists, maps, sets, sorted sets, HyperLogLogs, bitmaps, streams, and spatial indexes.
The service combines the best of in-memory, schema-less design with optimized data structures and multiskilled modules that adapt to the user’s data needs. It results in a high performance, multi-purpose database, that scales easily like a simple key-value data store but delivers sophisticated functionality. It also enables data persistence and high availability through replication and backups.
For additional information, visit their official webpage.