RPC

A Remote Procedure Call (RPC) allows a program to execute a procedure on another computer or server as if it were a local function call, abstracting away the complexities of network communication.

from xmlrpc.server import SimpleXMLRPCServer

def add(a, b):
    return a + b

def multiply(a, b):
    return a * b

server = SimpleXMLRPCServer(("localhost", 8000))
print("Listening on port 8000...")
server.register_function(add, "add")
server.register_function(multiply, "multiply")
server.serve_forever()

import xmlrpc.client

with xmlrpc.client.ServerProxy("http://localhost:8000/") as proxy:
    print("3 + 5 = %d" % proxy.add(3, 5))
    print("3 * 5 = %d" % proxy.multiply(3, 5))

gRPC

RPC vs gRPC

Feature	gRPC	RPC (General)
Data Serialization	Protocol Buffers (binary)	Various (JSON, XML, Protobuf)
Transport Protocol	HTTP/2 (primarily)	Varies (TCP, UDP, HTTP)
Performance	Generally faster	Varies depending on implementation
Streaming	Supports streaming	May or may not support streaming
Complexity	Steeper learning curve	Varies, can be simpler
Language Support	Good support for many languages	Varies, depends on implementation
Microservices	Well-suited for microservices	Can be used for microservices, but may not be the best choice

In essence: gRPC is a modern, high-performance RPC framework built for efficient communication, especially in distributed systems and microservices. While traditional RPC is a broader concept, it can be less performant than gRPC due to its reliance on potentially less efficient data formats and transport protocols.