For quite some time relational databases, such as MySQL, Oracle and Microsoft SQL Server, have been used to store data for most applications. While they are indeed ACID compliant (meaning interrupted database transactions won't result in lost data or similar nasty surprises) and good at avoiding redundancy, they are difficult to scale horizontally (across multiple servers) and can be slow for certain tasks. With the Web growing rapidly, spawning enourmous, user-generated content websites such as Facebook and Twitter, fast databases that can handle huge amounts of data are a must. For this purpose new databases management systems collectively called NoSQL are being developed. This thesis explains NoSQL further and compares the write and retrieval speeds, as well as the space efficiency, of two database management systems from the document oriented branch of NoSQL called MongoDB and CouchDB, which both use the JavaScript Object Notation (JSON) to store their data within. The benchmarkings performed show that MongoDB is quite a lot faster than CouchDB, both when inserting and querying, when used with their respective Python libraries and dynamic queries. MongoDB also is more space efficient than CouchDB.