Martin Fowler & Pramod Sadalage
Some common characteristics of NoSQL databases
1. they don’t use the relational data model, and thus don’t use the SQL language
2. they tend to be designed to run on a cluster
3. they tend to be Open Source
4. they don’t have a fixed schema, allowing you to store any data in any record

Interesting read on Martins bliki and


Framework vs Library

A library is essentially a set of functions that you can call, these days usually organized into classes. Each call does some work and returns control to the client.

A framework embodies some abstract design, with more behavior built in. In order to use it you need to insert your behavior into various places in the framework either by subclassing or by plugging in your own classes. The framework’s code then calls your code at these points.

source: Martin Fowler