guess which of the two domains oh the features came from so it's a lot like the real versus fake discriminator and ends and then the feature extractor you can think of as loosely analogous to the generator in games except what's trying to do here is both fool the domain recognizer and two not knowing which domain the data came from and also extract features that are good for classification so at the end of the day you can in in the cases where it works out you can actually get features that work about the same in both domains