gRPC ( # REST ) but + Google Protocol Buffer ( binary )
RPC Definition:
Remote Procedure Call (RPC) is a protocol that one program can use to request a service from a program located in another computer on a network without having to understand the network's details.
A procedure call is also sometimes known as a function call or a subroutine call.
Tutorialspoint:
https://www.tutorialspoint.com/xml-rpc/xml_rpc_intro.htm
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