This document provides an overview of CouchDB, a document-oriented NoSQL database. It begins with an introduction comparing relational and NoSQL databases, and describing the different types of NoSQL databases. The bulk of the document then focuses on CouchDB, explaining that it is document-oriented, uses JSON documents, and features MapReduce queries, HTTP API, replication, and eventual consistency. It also provides overviews of CouchDB's architecture, how it stores documents, and related projects like PouchDB. The document concludes with screenshots of the CouchDB interface and references.