Microsoft Azure Cosmos DB (formerly known by Document DB) is Microsoft’s globally distributed multi-model database service. It is purely Platform as a Service offering (meaning– you don’t need to spin up a VM for Cosmos DB). Microsoft started Project “Florence” in the year 2010 released as Document DB service with a vision of document-based database. Azure Storage Table offering is already providing a facility for storing the data in a key-value pair. After embracing open source technologies in Azure, Microsoft also started supporting NoSQL databases like MySQL, Cassandra, Mongo DB and Azure MySQL as well.