Redis Server simplifies development by providing a ready-to-run version of Redis, now you can manage the Redis service easily (start, stop, restart, launch at login, etc.).
Redis is a data structure server. It is open-source, networked, in-memory, and stores keys with optional durability. (see http://redis.io/ )
If you are developing web applications that utilize Redis, Redis Server is for you!
Note: Redis listens on port 6379 by default.