- model contains the layers of the network and its weights/biases, and some status flags (e.g. trainable) - it’s the same in any DL framework.
- Learner (and its subclasses) is a fastai “feature” that binds together data and model, optimizer, etc. and makes it easy to do almost everything a DL practitioner needs through a single interface.
So a good metaphor would be a bus - Learner is the driver console, model is perhaps the engine, and there are many other parts to the bus. And you Daniel are its driver that controls them all via that console that is Learner.