The first lesson is image classification ("is this a picture of a cat or a dog?"). Given that OP is commenting on an object detection library release, though, I

The first lesson is image classification ("is this a picture of a cat or a dog?"). Given that OP is commenting on an object detection library release, though, I assume they're interested in object recognition/detection/segmentation and rather than just image classification. So, more like: "what things are in this image and where are they?" or even just "where are the dogs in this image?" That's also covered eventually in fast.ai, but not until the second course if memory serves.