What is gRPC?
Learn the core principles of gRPC, its origins, and how it leverages HTTP/2 for efficient communication.
What is gRPC? is a free gRPC & High Performance APIs lesson on CoddyKit — lesson 2 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the gRPC & High Performance APIs learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Discovering gRPC
Meet gRPC, a high-performance framework for modern APIs. Built for speed and efficiency, it's a great fit for distributed systems and microservices.
Understanding Remote Procedure Calls
RPC (Remote Procedure Call) lets you invoke a function on another machine as if it were local — client sends a request, server runs it and replies.
RPC: A Local Call, Remotely
Imagine calling add(5, 3) when add lives on a remote server. RPC hides every network detail so it feels like a plain local call.
Why gRPC for Modern APIs?
gRPC beats plain REST for internal microservices: faster via HTTP/2 and binary serialization, strongly typed to prevent format errors, and multi-language.
HTTP/2 Powers gRPC
A big reason for gRPC's speed is HTTP/2. Unlike HTTP/1.1's one-at-a-time exchange, HTTP/2 carries many requests and responses over a single connection at once.
Binary & Multiplexing
HTTP/2 uses binary framing (cheaper to parse than text) and multiplexing, so requests and responses interleave on one connection without blocking.
Protocol Buffers: Data Definition
Protocol Buffers are gRPC's IDL and serialization format. You define services and messages in a .proto file, then compile it into code for many languages.
RPC vs. REST (Brief Look)
Quick contrast: REST is resource-oriented over HTTP methods with JSON, while gRPC is service-oriented using Protobuf over HTTP/2 — ideal for internal, high-perf calls.
Why Choose gRPC?
gRPC wins on four fronts: high performance from HTTP/2 and Protobuf, code generation with strong typing, language-agnostic services, and built-in streaming.
Quick Check on gRPC
Which of the following are key characteristics or technologies used by gRPC?
What We Learned About gRPC
You've got gRPC: a high-performance RPC framework on HTTP/2, using Protocol Buffers for interfaces, with speed, strong typing, and language interop. Next: a deeper REST comparison.
Frequently asked questions
Is the “What is gRPC?” lesson free?
Yes — the full text of “What is gRPC?” is free to read here on the web, and the gRPC & High Performance APIs course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the gRPC & High Performance APIs course, upgrade to CoddyKit PRO.
What will I learn in “What is gRPC?”?
Learn the core principles of gRPC, its origins, and how it leverages HTTP/2 for efficient communication. You practise gRPC & High Performance APIs with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start gRPC & High Performance APIs?
No prior experience is required. gRPC & High Performance APIs on CoddyKit is structured for beginners through advanced learners; this is — lesson 2 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “What is gRPC?” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this gRPC & High Performance APIs lesson?
Yes. Every gRPC & High Performance APIs lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.