Design a key value store ( distributed )

http://blog.gainlo.co/index.php/2016/06/14/design-a-key-value-store-part-i/
http://blog.gainlo.co/index.php/2016/06/21/design-key-value-store-part-ii/

Redis
http://www.slideshare.net/dvirsky/introduction-to-redis
Data Models
http://www.slideshare.net/oemebamo/introduction-to-memcached
http://www.slideshare.net/mdirolf/introduction-to-mongodb