An important aspect of Redis is the key-value pair. Redis calls itself an in-memory data-structure store. In simple terms, Redis is not a full-blown DBMS. It can persist data on disks, and does so to save its state, but its intended use is to optimally use memory and memory-based methods to make a number of common data structures very fast for lots of users. Redis supports the following data structures: strings, hashes, lists, sets, and sorted sets.

The flexibility of Redis permits a wide diversity of how keys are structured and saved. The performance and maintainability of Redis can be either positively or negatively impacted by the choices made in designing and constructing the Redis keys applied in one's database. A good general practice when designing one's Redis keys is to construct at least a rough outline of what information you are trying to store in Redis and an initial idea of how the data will be stored in one of the many different Redis data structures.