What is Middleware?

Middleware is a component of a computer system or network that exists in the middle of the system, often to add to the functionality of the entire platform. Middleware can also be considered the service layer. In a blockchain context, middleware is made up of various systems that help decentralized applications (dApps) expand their utility. In blockchain, examples of middleware include smart contracts, oracles, databases, digital identities, file storage, and various connectivity devices. The service layer is also made up of application programming interfaces (APIs), multi-signature technology, digital assets, blockchain governance systems, and other components.