1Redis is an open source, advanced key-value store. It is often referred 2to as a data structure server since keys can contain strings, hashes, 3lists, sets and sorted sets. 4 5You can run atomic operations on these types, like appending to a string; 6incrementing the value in a hash; pushing to a list; computing set 7intersection, union and difference; or getting the member with highest 8ranking in a sorted set. 9 10In order to achieve its outstanding performance, Redis works with an 11in-memory dataset. Depending on your use case, you can persist it either 12by dumping the dataset to disk every once in a while, or by appending each 13command to a log. 14 15Redis also supports trivial-to-setup master-slave replication, with very 16fast non-blocking first synchronization, auto-reconnection on net split 17and so forth. 18