Gun is an open-source and realtime, decentralized, offline-first, graph database engine written in JavaScript. It is designed to be small and simple for fast data synchronization which runs everywhere JavaScript is supported. Gun is a fully distributed database aiming at scaling web application and correctly synchronizing data among devices with offline-first feature.
Gun was built by Mark Nadal in 2014. He spent 4 years researching scaling up his web application, and eventually he found out it was hard with traditional databases or Master-Slave databases because of one big bottleneck, and decided to create Gun, a P2P database which can run on any browsers.