Definition: XML-RPC protocol is used for inter-process communication. It's part of the W3C's REST API standard, enabling dynamic exchange between clients and servers via APIs. Specifically, it allows client code to interact with server-side services directly through XML RPC messages. Definition: XML-RPC (Extensible Markup/Representational State Transfer) protocol is a high-level programming interface for exchanging structured data in the Web service model. In essence, it's a way of defining and specifying how you want to communicate between clients and servers on the Internet through XML. It enables clients and servers to establish and maintain client-server sessions over a network. The server can provide services (e.g., HTTP requests) or perform tasks (e.g., HTTP responses). In return, the client sends requests in XML format and expects an appropriate response in XML format from the server.