"gRPC is a platform-neutral RPC system that uses the Protocol Buffers IDL to define end-point services and message payloads to be transferred, then generating stubs for multiple languages. gRPC supports 10 languages - C, C++, C#, Go, Java (including Java/Android), Node.js, Objective-C, PHP, Python, and Ruby – on Linux, Mac and Windows. There are native implementations in C, Go and Java, and wrappers around the C library for the other languages."
GitHub - grpc/grpc: The C based gRPC (C++, Node.js, Python, Ruby, Objective-C, PHP, C#)
"Remote Procedure Calls (RPCs) provide a useful abstraction for building distributed applications and services. The libraries in this repository provide a concrete implementation of the gRPC protocol, layered over HTTP/2. These libraries enable communication between clients and servers using any combination of the supported languages."
"Protocol Buffers (a.k.a., protobuf) are Google's language-neutral, platform-neutral, extensible mechanism for serializing structured data. You can find protobuf's documentation on the Google Developers site."
gRPC Basics - C#
"what is behind this improvement. There are two major factors at work here: more efficient data encoding and HTTP/2. gRPC keeps data in binary both in client memory and on the wire by building on HTTP/2 and Protocol Buffers. This eliminates processing and space required for string encoding schemes such as Base64 or JSON. In addition, HTTP/2 itself makes things go faster with multiplexed requests over a single connection and header compression."