Meet Planetmint. The metadata blockchain.
It has some database characteristics and some blockchain properties <properties.html>_, including decentralization, immutability and native support for assets.
At a high level, one can communicate with a Planetmint network (set of nodes) using the Planetmint HTTP API, or a wrapper for that API, such as the Planetmint Python Driver. Each Planetmint node runs Planetmint Server and various other software. The terminology page <terminology.html>_ explains some of those terms in more detail.