FIDL (Fuchsia Interface Definition Language) is the IPC system for Fuchsia.
The language tutorials presents a simple “Hello, world” client and server, showing the FIDL language definitions and continuing with sections specific to each supported target language (e.g., C++, Dart).
Read the concepts doc to get a brief overview of what FIDL is, including some of its design goals, requirements, and workflow.
The bindings reference includes references of generated code in each binding and the FIDL utility libraries available to each language.
The language reference is for everything else, like the wire format and FTPs.
Please read the contributing doc for more information.