Introduction

In computing, NoSQL is a term used to designate database management systems that differ from classic relational database management systems in some way. These data stores may not require fixed table schemas, and usually avoid join operations and typically scale horizontally. Academics and papers typically refer to these databases as structured storage, a term that would include classic relational databases as a subset.

Notable production implementations include Google's BigTable, Amazon's Dynamo and Cassandra used by Facebook and others.

References

1. http://en.wikipedia.org/wiki/NoSQL