RESTful and command-line APIs

For external clients and applications to interact with the blockchain, its ledger, and smart contracts, most platforms offer both a CLI (command-line interface) and a RESTful API (application programming interface). Such interfaces define a set of functions that developers can use to perform certain actions on the blockchain and receive responses via the HTTP protocol using the GET and POST method. The two interfaces differ in terms of functions supported. For example, you can use the command-line interface to control the settings of your node, whereas RESTful APIs can be used to invoke and query data on the blockchain. More advanced blockchain platforms also offer SDKs (Software Development Kits) for specific programming languages that are an abstraction layer on top of these APIs.