Personally I haven’t extensively used redis. My limited understanding of redis would be summarized as: redis is in-memory database, stored in RAM (making use of underutilized RAM space in servers) being stored in primary RAM it’s very fast being stored in volatile storage (RAM) it vanished as system goes off, however there are ways to persist it in the file system redis uses key value storage and supports quite a few datatypes including list, hashmaps, geocodes, etc how companies like twitter have made an extensive use of redis in caching for faster retrieval (low latency when the throughput demand is high) it can be used as pub-sub model (message broker) Trivia: Redis is an acronym for “Remote Dictionary Server”