CouchDB is an Apache OpenSource project. It is Damien Katz's brain child and has a number of very attractive features based on very cool technologies. Such as ... RESTful API Schema-less document store (document in JSON format) Multi-Version-Concurrency-Control model User-defined query structured as map/reduce Incremental Index Update mechanism Multi-Master Replication model Written in Erlang (Erl
![CouchDB Implementation](https://cdn-ak-scissors.b.st-hatena.com/image/square/baa9c2e0054aeb33db772a041a3bd5f05ecebeef/height=288;version=1;width=512/http%3A%2F%2F1.bp.blogspot.com%2F_j6mB7TMmJJY%2FSPvy8vNVzbI%2FAAAAAAAAADY%2FDBjZepLYw3E%2Fw1200-h630-p-k-no-nu%2FP1.png)