A Remote Procedure Call (RPC) is a protocol that allows a program to execute a procedure on a different computer as if it were a local call. This enables communication between different systems over a network, making it easier for applications to interact with each other without needing to understand the underlying network details. RPC works by sending a request from the client to the server, which processes the request and sends back the result. This method simplifies the development of distributed applications, as developers can focus on the functionality rather than the complexities of network communication.