Ask Miss O11y: Making Sense of OpenTelemetry: Who's There? The Resource.
Ah, I too have wondered about this. TL;DR: The Resource says what program is sending these spans and where it’s running. You can skip it if you define OTEL_SERVICE_NAME in the environment. When I’m setting up tracing (for instance, in a Node.js app), I have to create a Resource object in order to set up the OpenTelemetry SDK: If I don’t define that resource parameter, then tracing will still work. But my spans will show up with aservice.name of unknown_service:node.