and you teach a model to predict which line of transport is running on a given image tile your model is going to learn the Vienna transport network it's going to be an absolute expert and you can then take this model you can take this CNN that knows everything about the Vienna transport network and put it back into our original architecture replacing the CNN from before the CNN that had to be trained from scratch our model now does need to be trained from scratch it has a big big head start it has a quiet general understanding so it just needs