- Redis is an open source, advanced key-value store that can store different data structures like strings, hashes, lists, sets and sorted sets. - Jedis is the recommended Redis client library for Java. It can be used to connect to Redis and execute commands to set, get, and manipulate Redis data structures. - The document provides examples of common Redis commands to work with strings, lists, sets, sorted sets, hashes, publish/subscribe and more using the Jedis client.